CSAT (GS Paper II) 2017

Answer: (c) Environmental issues contribute to resource stresses and political conflict.

The passage traces a chain: climate change shrinks resources, and the scramble for what remains turns into political or even violent conflict, often disguised as identity or ideology. Option (c) states exactly this link between environmental stress, scarce resources and conflict.

• ✗ (a) The passage says resource conflicts wear a politically palatable 'veneer'; it never says politics is their motive, and 'always' is far too strong.
• ✗ (b) Solutions are not discussed at all; the passage only explains how such conflicts arise and how they are disguised.
• ✓ (c) Climate change 'hastens the reduction of resources', and competition over them takes the form of 'political or even violent conflict' — environment, then resource stress, then conflict.
• ✗ (d) Whether identity-based conflict can be resolved is never discussed; the passage only says resource conflicts are cloaked as identity or ideology.

Remember · For 'imply' questions, choose the option that restates the passage's cause-and-effect chain; reject options about solutions the passage never discusses.

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Answer: (a) we should first consult wisely and then resolve firmly

The passage rejects two failures — endless hesitation, and a resolve that bends at the first suggestion — and names the only route to eminence: consult wisely first, then resolve firmly, then persevere. Option (a) keeps this sequence; the others drop the consulting step or add ideas of their own.

• ✓ (a) It restates the passage's key sentence: the man who 'first consults wisely, then resolves firmly' is the one who advances.
• ✗ (b) The passage does not ask us to reject a friend's advice; it criticises changing a decision at the 'first counter-suggestion'. Wise consultation is itself part of the formula.
• ✗ (c) Broad-mindedness is never discussed; if anything, veering 'from opinion to opinion' is criticised.
• ✗ (d) Firmness is part of the message, but this option leaves out wise consultation, which the passage puts first; 'achievement-oriented' is the reader's own addition.

Remember · When a passage lays down a sequence of steps, the keynote must keep that sequence; an option built on one step alone is incomplete.

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Answer: (d) Climate change poses a threat to the survival of polar bears.

Summer sea ice in the Arctic is melting earlier and faster and has shrunk by about 30 per cent, and this threatens the food web topped by polar bears. The crucial message is that a warming Arctic endangers polar bears.

• ✗ (a) The passage says the period of summer melt is lengthening, not that summer has become short; temperatures are not mentioned.
• ✗ (b) Moving polar bears elsewhere is an outside idea; the passage offers no remedy.
• ✗ (c) This reverses the passage: the food web is threatened by ice loss, and polar bears stand at its top. Their absence is not said to destroy the food chains.
• ✓ (d) Earlier, faster melting (a climate-change signal) undermines the food web 'atop which stand polar bears', so their survival is at risk.

Remember · Crucial message = the passage's main consequence. Watch for options that flip cause and effect or bring in remedies the passage never mentions.

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Answer: (b) People have to perceive toilet use and pit-emptying as clean and not polluting.

The passage finds two reasons why people avoid toilets — ideas of purity and pollution, and dislike of emptying pits — and says these must be confronted to end open defecation. So people's view of toilet use and pit-emptying as polluting has to change.

• ✗ (a) The passage says these ideas 'have to be confronted and dealt' with, which assumes they can change, not that they are permanent.
• ✓ (b) The two barriers are notions of pollution and reluctance to empty pits; confronting them means people must come to see toilet use and pit-emptying as clean.
• ✗ (c) Too sweeping; the passage's point is that the practice can be ended if its causes are tackled.
• ✗ (d) Civic sense and privacy are not discussed; the reasons given are purity-pollution beliefs and pit-emptying.

Remember · When a passage names the causes of a problem and says they must be confronted, the crucial message concerns changing those very causes.

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Answer: (b) The growth driven by GDP only is neither desirable nor sustainable.

World GDP grew by 50 per cent while inclusive wealth grew by only 6 per cent, and natural capital actually fell by 30 per cent. GDP-driven growth is eating into the wealth it rests on, so growth driven by GDP alone is neither desirable nor sustainable.

• ✗ (a) Natural capital is only one part of the story; the passage's criticism is of GDP-driven growth as a whole, which also held back human capital.
• ✓ (b) GDP rose sharply while inclusive wealth barely moved and natural capital shrank — growth measured by GDP alone harms human and natural capital, so it can neither last nor be welcomed.
• ✗ (c) The passage does not judge the countries' economic performance in general — GDP in fact grew by 50 per cent. It questions the kind of growth.
• ✗ (d) Human capital grew slowly, but the passage does not argue that the world needs more of it; its target is GDP-only growth.

Remember · For the 'most crucial inference', prefer the option that captures the whole contrast (here GDP versus inclusive wealth), not one fragment of the data.

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Answer: (b) Labour reforms are required in India to make optimum use of its vast labour force productively.

India has a large youth surplus, but 93 per cent of its labour force is in the unorganized sector and job creation lags behind the growth of the labour force. The passage presents labour reforms as the way to put this workforce to productive use.

• ✗ (a) Population control is not discussed; the surplus of young people is presented as an opportunity, not a problem to curb.
• ✓ (b) Labour reforms are 'often cited as the way' to unlock growth, in the context of a huge but mostly unorganized labour force and too few new jobs.
• ✗ (c) Employment growth has slowed to 0.5 per cent and new jobs trail the labour force; nothing suggests double-digit growth is near.
• ✗ (d) The passage says India 'could fill the gap' in young people, but says nothing about their skills.

Remember · Rational inference = where the passage's data and argument point. Discard options that add a new quality (here 'skilled') or a new remedy.

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Answer: (a) it is essential for human beings to work

The passage calls complete freedom from work unnatural, says that escaping work only throws the burden on someone else, and warns that mankind would starve if it stopped working. Its main idea is that work is essential for human beings.

• ✓ (a) Every sentence leads here: freedom from work is 'unnatural', and the human race 'shall perish of famine' if it stops working.
• ✗ (b) The closing line asks how much leisure we can afford, but only as a follow-up to the main point that work cannot be escaped.
• ✗ (c) 'Tyranny' describes nature's rule that we must work; it is a supporting phrase, not the main idea.
• ✗ (d) Our 'understanding' of work is not the subject; the passage asserts the necessity of work itself.

Remember · Main idea = the claim most sentences support. A striking word from the passage, or its closing question, is rarely the main idea by itself.

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Answer: (c) make it easier for us to live

The author says habits 'simplify the mechanism of life' and let us do many things automatically; without them existence would be 'an impossible confusion'. So habits make it easier for us to live.

• ✗ (a) The opposite of the passage, which says we 'could not get on without them'.
• ✗ (b) Precision is not mentioned; the benefit described is ease — not having to think afresh every time.
• ✓ (c) Habits simplify life and spare us fresh thought for every routine act, so they make living easier.
• ✗ (d) The passage does speak of the 'mechanism of life' and of doing things automatically, but as a help, not as a complaint that habits mechanize life.

Remember · Match the author's attitude: a passage that praises something will not support an option that criticises it, even if the option borrows the passage's words.

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Answer: (b) There is at least one supporter of ‘party Y’ who knew some supporters of ‘party X’ as a friend.

The information is about a group of party X supporters who knew Z and backed his campaign strategy, and it says some of them had friends in party Y. So at least one person in party Y has a party X supporter as a friend.

1. Call the group described G: supporters of party X who knew Z and supported his campaign strategy.
2. 'Some of them had friends in party Y' tells us that G is not empty and that at least one member of G has a friend in party Y.
3. Friendship works both ways, so that person in party Y knows a supporter of party X as a friend — option (b).
4. Check (c) and (d): G itself consists of party X supporters who knew Z and backed his strategy, so both 'No …' statements are false.

• ✗ (a) The information says nothing about how party Y's supporters viewed the alliance; it speaks only of party X supporters.
• ✓ (b) Some members of the group had friends in party Y, so at least one person in party Y counts a party X supporter as a friend.
• ✗ (c) The group described consists of party X supporters who did support Z's strategy, so this is false.
• ✗ (d) The same group knew Z, so it is false that no party X supporter knew Z.

Remember · 'Some of them' confirms the group exists. A 'No …' statement fails as soon as one member of that group is shown to exist.

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Answer: (c) 3 only

The information confirms that some party X supporters knew Z and supported his strategy. That makes statement 1 true and statement 3 false. Statement 2, about supporters who opposed the strategy, is neither confirmed nor contradicted, so only statement 3 can be called not correct.

1. From 'some of them had friends in party Y', there exist party X supporters who knew Z and supported his strategy.
2. Statement 1: some party X supporters knew Z — true.
3. Statement 3: it says no party X supporter backed Z's strategy — this contradicts the information, so it is not correct.
4. Statement 2: the information is silent about supporters who opposed the strategy, so it cannot be marked incorrect; it is simply not established.
5. Only statement 3 is not correct.

• ✓ 1. The supporters described knew Z, so 'some supporters of party X knew Z' must hold.
• ✓ 2. Not contradicted: the information says nothing about supporters who opposed the strategy, so this may well be true and cannot be called incorrect.
• ✗ 3. The information describes party X supporters who did support Z's campaign strategy, so this statement is false.

Remember · 'Not correct' means contradicted by the information. A statement the information is merely silent about is not proved wrong.

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Answer: (b) 22

Working days are fewest in a short month with many holidays. Every month has exactly two holiday Saturdays, so only the Sundays vary: a 28-day February has exactly 4 Sundays, giving 6 holidays and 22 working days. Longer months add more days than holidays.

1. Every month has a 2nd and a 4th Saturday, so there are always exactly 2 holiday Saturdays; only the number of Sundays varies.
2. February (28 days): exactly 4 Sundays → 4 + 2 = 6 holidays → 28 − 6 = 22 working days.
3. February in a leap year (29 days): at most 5 Sundays → 7 holidays → 29 − 7 = 22 working days.
4. 30-day month: at most 5 Sundays → 7 holidays → 23 working days. 31-day month: at most 5 Sundays → 7 holidays → 24.
5. Minimum = 22.
6. Check: no month can have 6 Sundays, since that needs at least 36 days.

Remember · For 'minimum working days', test the shortest month with the most holidays — February, including the leap-year case.

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Answer: (d) 64/729th part of the population

Each year one-third leaves, so two-thirds of the previous year's population remains. The fraction compounds, so after six years the population left is (2/3)⁶ = 64/729 of the original.

1. After one year, 1 − 1/3 = 2/3 of the population remains.
2. The same fraction applies to what is left each year, so after 6 years the remainder is (2/3)⁶.
3. (2/3)⁶ = 2⁶/3⁶ = 64/729.
4. Check: the denominator must be 3⁶ = 729 and the numerator 2⁶ = 64; only (d) has both.

Remember · Repeated fractional loss compounds: after n rounds of losing 1/k, the remainder is (1 − 1/k)ⁿ, not 1 − n/k.

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Answer: (c) Mathematics

Chemistry is on day 3. Biology cannot be last, since a test follows it, and cannot be first, since Physics must come before the test after Biology. So Biology is on day 2, Physics on day 1, and Mathematics is left for day 4.

1. 'Exactly after two tests are held' puts Chemistry on day 3.
2. Some test is held after Biology, so Biology is not on day 4.
3. If Biology were on day 1, the test after it would be on day 2, and Physics would have to be on day 1 — already taken. So Biology is not on day 1.
4. So Biology is on day 2; the test after it is Chemistry (day 3), and Physics is before that — day 1.
5. Order: Physics, Biology, Chemistry, Mathematics. The last test is Mathematics.

Remember · Fix the absolute clue first (a definite day), then test the remaining slots against each relative clue.

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Answer: (b) B

A is half of B + D, and A + C equals B + D, so C = A. Then A + B > C + D gives B > D, and since A is the average of B and D, B is above A. B has the highest income.

1. A = (B + D)/2, so B + D = 2A.
2. A + C = B + D = 2A, so C = A.
3. A + B > C + D becomes A + B > A + D, so B > D.
4. A is the average of B and D with B > D, so B > A > D. With C = A, the order is B > A = C > D.
5. B has the highest income.

Remember · Turn each sentence into an equation or inequality and substitute; one equality (here C = A) usually unlocks the ranking.

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Answer: (a) Only conclusion I follows from the statement.

The statement says that even a natural gift like a good voice must be practised to improve and excel — that is, a gift needs nurturing. It says nothing about people whose voice is not good, so only Conclusion I follows.

1. The statement: a good voice is a gift, yet it must be practised to improve and excel.
2. Conclusion I generalises this correctly — a natural gift still needs nurturing — so it follows.
3. Conclusion II is about people without a good voice, whom the statement never mentions, so it does not follow.

• ✓ I Practising 'to improve and excel' is exactly the nurturing and care the conclusion speaks of.
• ✗ II The statement concerns only people who have a good voice; whether others should practise lies outside it, however sensible it sounds.

Remember · A conclusion must come from the statement itself; one about a group the statement never covers does not follow.

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Answer: (b) 163 cm

A spider does not slip back in the chance in which it reaches the top, so height = 39 net gains + one full climb. That gives X = 201 cm, Y = 163 cm and Z = 182 cm; the shortest pillar is 163 cm.

1. Net gain per chance: A = 6 − 1 = 5 cm, B = 7 − 3 = 4 cm, C = 6.5 − 2 = 4.5 cm.
2. In the 40th chance each spider reaches the top and does not slip, so height = 39 × (net gain) + (full climb).
3. X = 39 × 5 + 6 = 201 cm; Y = 39 × 4 + 7 = 163 cm; Z = 39 × 4.5 + 6.5 = 182 cm.
4. Shortest pillar = 163 cm (Y).
5. Check for Y: after 38 chances B is at 152 cm and reaches only 159 cm in the 39th climb, so it truly needs the 40th.

Remember · Climb-and-slip problems: the last climb has no slip. Height = (n − 1) × net gain + one full climb.

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Answer: (c) Rights aim at both individual and social good.

The definition joins two ideas: rights are conditions of social well-being, and they are indispensable to the true development of the individual citizen. So rights serve both the individual and society.

• ✗ (a) It drops 'social well-being', which the definition names as what rights are conditions of.
• ✗ (b) It drops 'the true development of the citizen', the individual purpose in the definition.
• ✓ (c) Social well-being (society) and the citizen's development (individual) both appear in the definition.
• ✗ (d) It contradicts the definition by cutting rights off from social well-being.

Remember · When a definition names two beneficiaries, reject 'only' options that keep just one of them.

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Answer: (c) 16th

Only the 52 − 15 = 37 students who passed are in the merit list. With 21 above Ramesh, 37 − 22 = 15 are below him, so he is 16th from the bottom.

1. Students in the merit list = 52 − 15 = 37.
2. Position from bottom = total − position from top + 1 = 37 − 22 + 1 = 16.
3. Check: 21 above + Ramesh + 15 below = 37.

Remember · Rank from top + rank from bottom = total + 1 — but first count only those actually in the list.

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Answer: (c) Q is the father of P.

P + R means P is the son of R, and R − Q means R is the wife of Q. So Q is the husband of P's mother R, which makes Q the father of P.

1. P + R → P is the son of R.
2. R − Q → R is the wife of Q, so Q is R's husband.
3. P is the son of R, and R's husband is Q, so Q is the father of P.

Remember · Decode coded relations one link at a time, left to right, noting each person's gender as you go.

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Answer: (c) Gain 1%

Take Gopal's cost as ₹100. Ram pays ₹110 and offers the phone back at 10% less, ₹99 — ₹1 below what Gopal first paid, a 1% gain. UPSC's options compare this buy-back price with Gopal's original cost.

1. Let Gopal's cost be ₹100.
2. Sold to Ram at 10% profit: ₹110.
3. Ram sells it back at 10% loss on his cost: 110 × 0.9 = ₹99.
4. Gopal gets back for ₹99 the phone that first cost him ₹100: a gain of ₹1 on ₹100 = 1%.
5. Note: counting both deals, Gopal ends ₹11 ahead (+110 − 99); no option matches that, so the options measure only the buy-back price against his original cost.

Remember · A rise of x% then a fall of x% leaves the price x²/100 % below the start: 10% up, 10% down → 1% lower.

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Answer: (d) hard work, brotherhood and national unity

The passage opens with 'hard work ahead', calls all Indians, whatever their religion, equally the children of India, and warns that a narrow-minded people cannot make a great nation. Its challenge is hard work, brotherhood and national unity.

• ✗ (a) 'High standard' in the passage means living up to the country's greatness, not a standard of living; privileges are not held out as the goal.
• ✗ (b) Equal privileges are stated as something citizens already share, not as a goal; 'political tolerance' is not the passage's concern — it speaks against communalism and narrow thinking.
• ✗ (c) Neither a spirit of adventure nor economic parity is mentioned.
• ✓ (d) 'Hard work ahead' (hard work), 'equally the children of India' (brotherhood), and the rejection of communalism and narrow-mindedness (national unity).

Remember · When options list three ideas, all three must be in the passage; one unsupported item sinks the option.

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Answer: (c) the collective good as distinct from private wills of the individuals

Each individual places himself under the 'supreme direction' of the General Will and becomes 'an indivisible part of the whole'. The General Will is therefore the will of the community as one body, standing above and apart from each person's private will.

• ✗ (a) A 'sum total' keeps private wills separate and merely adds them; the passage speaks of an indivisible whole that directs each individual.
• ✗ (b) Elected representatives are not mentioned; the General Will belongs to the whole body of members.
• ✓ (c) Individuals put their power 'in common' under its supreme direction, so it is a collective good distinct from their private wills.
• ✗ (d) Material interests are not mentioned; the passage is about how the whole political community directs its members.

Remember · In quotation-based items, let the key phrases ('in common', 'indivisible part of the whole') decide, not outside knowledge.

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Answer: (d) In a mature democracy, force is narrowed down to a marginal phenomenon in the actual exercise of sovereignty.

Where people are politically mature, the law-making body and the organized will of the people seldom clash. With conflict rare, force is seldom needed — it shrinks to a marginal role, though it does not disappear.

• ✗ (a) It speaks of democracy in general and makes force central, the opposite of the passage's point about mature democracies.
• ✗ (b) If conflict seldom occurs, force cannot be the main phenomenon.
• ✗ (c) 'Seldom' is not 'never'; occasional conflict remains possible, so force is not wholly irrelevant.
• ✓ (d) Rare conflict between the sovereign body and the people means force is needed only occasionally — a marginal phenomenon.

Remember · Mind degree words: 'seldom' supports 'marginal', not 'irrelevant'. Extreme options overshoot the passage.

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Answer: (a) duty to vote

The passage calls deliberately staying away from voting 'a kind of implied anarchy' and a refusal of 'political responsibility'. Its subject is voting as an obligation — the duty to vote.

• ✓ (a) Not voting is described as dodging political responsibility while enjoying a free society's benefits, so voting is presented as a duty.
• ✗ (b) The entitlement to vote is not discussed; the passage criticises people who do not use it.
• ✗ (c) The freedom to vote or not to vote is not the theme; choosing not to vote is condemned.
• ✗ (d) Participation is mentioned, but as an obligation that sustains democracy, not as a right.

Remember · Words like 'responsibility' and criticism of those who abstain signal a duty, not a right or a freedom.

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Answer: (d) despair in a country sometimes leads to dictatorship

A dictator often reaches power by chance, and 'very often through the unhappy state of his country'. So despair in a country can lead to dictatorship.

• ✗ (a) It is others who can foresee a leader's rise from his character; the passage does not say he foresees it himself.
• ✗ (b) The passage contrasts leaders in free countries with dictators; it does not say only a free country chooses leaders.
• ✗ (c) No duty of a leader is discussed.
• ✓ (d) The 'unhappy state' of a country is named as a frequent route to power for a dictator; 'sometimes' keeps the claim within the passage.

Remember · Pick the option that restates a cause-and-effect link the passage gives; a modest qualifier ('sometimes') is safe when the passage says 'often'.

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Answer: (b) 2 only

The passage says technology's real gift is leisure, not material possessions, and that the creative use of leisure by a minority has driven all human progress. Assumption 2 restates this; assumption 1 goes against it.

• ✗ 1. The passage separates leisure from material possessions and notes that leisure may be abused by some; 'always' and 'acquiring more possessions' both go against it.
• ✓ 2. The 'creative use of leisure by a minority' being 'the mainspring of all human progress' is exactly this assumption.

Remember · 'Always' in an assumption is a warning sign; accept it only if the passage allows no exception.

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Answer: (d) Neither 1 nor 2

The passage values the study of famous battles for the lessons on leadership they hold — why winners won and losers lost. It says nothing about understanding modern warfare, and it does not make history essential for every aspiring leader.

• ✗ 1. The lessons drawn from battles concern the qualities of leaders, not modern warfare.
• ✗ 2. The passage says such study is beneficial and revealing; 'essential for anyone' goes further. The word 'necessary' in the quoted assertion is about interpreting current events, not about leadership.

Remember · Check the purpose the passage gives: an assumption that shifts the benefit to another goal, or hardens 'beneficial' into 'essential', is invalid.

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Answer: (c) 50 kg

The first five and the last five together cover all nine persons, with the 5th person counted twice. So the 5th person's weight = (5 × 45 + 5 × 55) − 9 × 50 = 500 − 450 = 50 kg.

1. Total of 9 persons = 9 × 50 = 450 kg.
2. First 5 = 5 × 45 = 225 kg; last 5 = 5 × 55 = 275 kg.
3. 225 + 275 = 500 kg, which counts the 5th person twice.
4. 5th person = 500 − 450 = 50 kg.

Remember · When two overlapping groups together cover everyone, (sum of the groups) − (grand total) = the overlap.

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Answer: (c) Nirmala

Two of the four Sociology postgraduates are bank employees. Amala and Komala are unemployed, so the two are Kamla and Nirmala. Nirmala is also a tennis player, so she is both.

1. Sociology postgraduates: Amala, Kamla, Komala, Nirmala — two of them are bank employees.
2. Amala and Komala are unemployed, so those two are Kamla and Nirmala.
3. Bank employees (three): Vimala, Kamla and Nirmala.
4. Tennis players include Komala and Nirmala; of these only Nirmala is a bank employee.
5. Check the other options: Amala and Komala are unemployed, and Shyamala is not one of the three bank employees.

Remember · In grouping puzzles, start with the clue naming a small closed set ('of whom two are…') and eliminate using the negative facts.

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Answer: (d) None of the above can be concluded with certainty.

P − Q = 0.15B − 0.10A, and its sign depends on how much bigger A is than B. If A is less than 1.5 times B, P is larger; if more, Q is larger; at exactly 1.5 times they are equal. So nothing can be concluded.

1. P − Q = (0.40A + 0.65B) − (0.50A + 0.50B) = 0.15B − 0.10A.
2. P > Q when 0.15B > 0.10A, i.e. A < 1.5B; Q > P when A > 1.5B; P = Q when A = 1.5B.
3. A > B allows all three: A = 1.2, B = 1 gives P > Q; A = 3, B = 1 gives Q > P; A = 1.5, B = 1 gives P = Q.
4. So the comparison cannot be fixed.

Remember · Subtract the two expressions and study the sign; if it depends on a ratio the question does not fix, the answer is 'cannot be determined'.

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Answer: (d) None of the above statements is correct.

Each day the two watches drift 4 minutes further apart. On a 24-hour dial they show the same time again only when the gap is a full 24 hours (1440 minutes), which takes 360 days. None of 30, 90 or 120 days works.

1. One watch loses 2 min and the other gains 2 min a day, so the gap between them grows by 4 min a day.
2. On a 24-hour clock the two dials match again when the gap reaches 24 × 60 = 1440 min.
3. Days needed = 1440 ÷ 4 = 360.
4. Check: after 120 days the gap is only 480 min (8 hours), so options (a) to (c) all fail.

Remember · Two clocks agree again when their total gap equals one full dial: 720 minutes on a 12-hour clock, 1440 minutes on a 24-hour clock.

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Answer: (b) 240

The 22% earning above ₹1,00,000 includes the 6% above ₹2,00,000, so 16% earn between ₹1,00,000 and ₹2,00,000. The 990 households between ₹30,000 and ₹1,00,000 are the remaining 66%, which makes 1500 households in all; 16% of 1500 = 240.

1. Above ₹1,00,000: 22%. Below ₹30,000: 12%. So ₹30,000–₹1,00,000: 100 − 22 − 12 = 66%.
2. 66% = 990 households, so the total = 990 ÷ 0.66 = 1500.
3. ₹1,00,000–₹2,00,000: 22% − 6% = 16% (the 22% already includes the 6% above ₹2,00,000).
4. 16% of 1500 = 240.

Remember · 'More than X' groups are cumulative; subtract the higher band to get the slab in between before converting to numbers.

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Answer: (b) 24 seconds

Why not the tempting option · UPSC's key, 24 seconds, treats the time as proportional to the number of strikes (2.4 s a strike). The textbook method counts the gaps between strikes — 4 gaps in 12 s, so 9 gaps at 10 o'clock make 27 s — but 27 is not among the options, so the paper plainly intends the simple proportion. In the exam, if the gap method gives no option, switch to proportion; (b) is the only option that fits the data.

UPSC's key takes the striking time as proportional to the number of strikes: 5 strikes take 12 seconds, so each strike accounts for 2.4 seconds and 10 strikes take 24 seconds. This is the only option that fits the data.

1. Read the data as 'each strike takes the same time': 12 s ÷ 5 strikes = 2.4 s a strike.
2. At 10 o'clock the clock strikes 10 times: 10 × 2.4 = 24 s, option (b).
3. Check the alternative: counting only the gaps between strikes (4 gaps of 3 s, then 9 gaps) gives 27 s, which is not offered, so that reading cannot be what the paper intends.

Remember · In a clock-strike question, first try the gap method (strikes − 1); if the result is not among the options, use simple proportion, as UPSC did here.

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Answer: (d) Neither 1 nor 2

'Good for health' says a morning walk helps. It does not say that every healthy person walks in the morning, nor that good health is impossible without it — so neither conclusion follows.

1. The statement gives a benefit: a morning walk improves health.
2. Conclusion 1 reverses it (healthy → morning walker); a benefit does not make the habit universal among healthy people.
3. Conclusion 2 upgrades 'good for' to 'essential'; there may be other ways to stay healthy.

• ✗ 1. It reverses the statement; healthy people may stay fit in other ways.
• ✗ 2. 'Good for' is not 'essential for'; the statement does not rule out other routes to good health.

Remember · 'Good for' never means 'essential for', and 'A helps B' never means 'all B do A'.

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Answer: (a) 47

The mean of five consecutive odd numbers is the middle (third) one, so the third number is 39 and the list starts at 35. The mean of thirteen consecutive odd numbers is the 7th number: 35 + 6 × 2 = 47.

1. Mean of 5 consecutive odd numbers = the 3rd number = 39, so the first number is 39 − 4 = 35.
2. The 13 numbers are 35, 37, …, 59 (35 + 12 × 2 = 59), all 2-digit.
3. Mean of an evenly spaced list = middle (7th) term = 35 + 6 × 2 = 47.
4. Check: (35 + 59) ÷ 2 = 47.

Remember · For an evenly spaced list, the mean equals the middle term, or the average of the first and last terms.

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Answer: (b) B, C and F

After all the transfers A has 8, B 7, C 12, D 15, E 11 and F 7 cards. D and E together hold 26, the same as B, C and F together (7 + 12 + 7).

1. Start: everyone has 10 cards.
2. F borrows 2 from A: A = 8, F = 12. F gives 5 to C: F = 7, C = 15.
3. C gives 3 to B: C = 12, B = 13. B gives 6 to D: B = 7, D = 16. D gives 1 to E: D = 15, E = 11.
4. D + E = 15 + 11 = 26.
5. B + C + F = 7 + 12 + 7 = 26. (A + B + C = 27, A + B + F = 22, A + C + F = 27.)
6. Check: total = 8 + 7 + 12 + 15 + 11 + 7 = 60, the same as at the start.

Remember · Track transfers in a small table and confirm the total stays unchanged — a quick guard against slips.

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Answer: (a) 25%

Take the one-third portion as 1 litre: it holds 0.5 litre of water. Adding 1 litre of pure milk makes 2 litres with the same 0.5 litre of water, which is 25%.

1. Let the portion taken (1/3rd of the sample) be 1 litre; at 50% water it has 0.5 litre of water.
2. Add an equal amount (1 litre) of pure milk, which has no water: total 2 litres.
3. Water = 0.5 ÷ 2 = 25%.

Remember · Adding an equal amount of the pure component halves the concentration; the size of the portion taken does not matter.

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Answer: (c) 36

Every rectangle, squares included, is fixed by choosing 2 of the 4 horizontal lines and 2 of the 4 vertical lines. That gives 6 × 6 = 36.

1. Ways to choose 2 horizontal lines from 4 = 4C2 = 6.
2. Ways to choose 2 vertical lines from 4 = 6.
3. Each pair of choices gives one rectangle: 6 × 6 = 36 (squares included).
4. Check: the grid has 3 × 3 unit cells; squares = 9 + 4 + 1 = 14 and non-square rectangles = 22; 14 + 22 = 36.

Remember · Rectangles in a grid of m horizontal and n vertical lines = mC2 × nC2; the squares are already included.

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Answer: (c) 240 km

The freight train has an 80 km lead when the express starts. The express closes the gap at 20 km/h, taking 4 hours, by which time it has run 60 × 4 = 240 km from Delhi.

1. Lead of the freight train when the express starts = 40 × 2 = 80 km.
2. Relative speed = 60 − 40 = 20 km/h, so time to catch up = 80 ÷ 20 = 4 h.
3. Distance of the express from Delhi = 60 × 4 = 240 km.
4. Check: the freight train has run 40 × 6 = 240 km in 6 hours.

Remember · Catch-up time = head start ÷ relative speed; then distance = the chaser's speed × that time.

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Answer: (d) Data are inadequate

Neha scores above Randhir, and Sonal above Shankar, but no clue compares Neha with Sonal. Either of them can come out on top, so the data are inadequate.

1. Clues: Randhir > Kunal + Debu; Kunal + Shankar > Randhir; Sonal > Shankar; Neha > Randhir.
2. Randhir is below Neha, and Kunal and Debu are below Randhir; Shankar is below Sonal. So only Neha or Sonal can be highest.
3. No clue links Neha and Sonal.
4. Example: Kunal 10, Debu 5, Randhir 20, Shankar 15, Sonal 16, Neha 25 — Neha is highest. Change Sonal to 30 and Sonal is highest. All clues hold both times.

Remember · In ranking puzzles, find who can still be on top; if two candidates are never compared, the data are inadequate.

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Answer: (a) Political development is not a unilinear process for it involves both growth and decay.

As traditional institutions and loyalties break down, some people cling afresh to traditional groups while others join new ones, and political development itself sharpens identities of class, tribe, region and religion. Change moves in more than one direction at once, so political development is not a straight, one-way process.

• ✓ (a) Old loyalties decay while new groups grow, and some old ties are even renewed — outcomes pull in different directions, so the process is not unilinear.
• ✗ (b) The passage does not say traditional societies succeed in resisting development; some people move to new groups.
• ✗ (c) 'Impossible' is contradicted by 'others align themselves with new groups'.
• ✗ (d) The passage does not call traditional loyalties helpful to development; it only records that some people renew them.

Remember · 'Best explanation' = the general principle behind the passage's examples. Mixed, opposite outcomes point to a 'not one-way' conclusion.

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Answer: (c) Devolution, to be successful, requires a democracy in which there is free expression of the will of the people at lower level and their active participation at the grassroots level.

The passage defines political legitimacy as a mass demand from below and says decentralization started from the top, without grassroots mobilization, often fails. So successful devolution needs people at the lower level to express their will and take an active part.

• ✗ (a) Powerful mass leaders are not mentioned; the passage stresses a demand arising from the masses themselves.
• ✗ (b) The opposite of the passage: decentralization initiated by the upper tier without grassroots support 'often does not fulfil its objectives'.
• ✓ (c) A 'mass demand from below' and political mobilization at the grassroots are what the passage makes necessary for success.
• ✗ (d) The passage wants a popular demand for decentralization, not a strong feeling of regionalism; regionalism is only the worldwide trend it describes.

Remember · If a passage says top-down action fails without X, the critical inference is that success requires X — not that the top should push harder.

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Answer: (b) Speaking of digital technologies is speaking of our life and living.

The passage says the digital is not just a tool but a condition that shapes who we are, how we connect, and our life, labour and language. So to speak of digital technologies is to speak of our life and living.

• ✗ (a) 'All problems of governance' is an extreme claim; the passage says only that the digital shapes our understanding of governance.
• ✓ (b) The digital 'has dramatically restructured our lives' and is 'a condition and context' of life, so talking about it is talking about how we live.
• ✗ (c) The passage says the digital shapes our imagination, not that creativity cannot be expressed without it.
• ✗ (d) The passage describes the present ('We live in digital times'), not what mankind's future existence requires.

Remember · For the 'essential message', prefer the option restating the passage's central image (the digital as a condition of life) over extreme claims.

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Answer: (a) Once a country reaches middle-income stage, it runs the risk of falling productivity which leads to stagnant incomes.

The IMF warns that fast-growing Asian economies risk the middle-income trap, in which incomes stop rising well short of Western levels, and names a collapse in productivity growth as its broad cause. Option (a) captures this chain of risk, falling productivity and stagnant incomes.

• ✓ (a) Middle-income trap = incomes stop growing; its overall cause = collapse in productivity growth. (a) links the two as a risk, as the passage does.
• ✗ (b) The passage speaks of a risk, not a general characteristic; not every fast-growing economy falls into the trap.
• ✗ (c) 'No hope at all' is extreme; a risk is not a certainty.
• ✗ (d) The passage does not grade Asian economies' present productivity record; it explains what could cause the trap.

Remember · 'Face the risk' supports an option framed as a risk; reject options that turn a risk into a certainty or a verdict.

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Answer: (c) Inclusive innovation and R&D can help create an egalitarian society.

The passage presents inclusive innovation and R&D as tools to check rising inequality — by focusing on the needs of the poor, lowering costs and creating earning opportunities. The assumption beneath it is that they can help build a more equal society.

• ✗ (a) The passage mentions pressures of rapid urbanization but never migration, and 'only way' is extreme.
• ✗ (b) 'Every rapidly growing country' generalises beyond the passage, which is about India.
• ✓ (c) Innovation 'can mitigate increases in social inequality' and create income for the poor — an egalitarian aim.
• ✗ (d) The link between urbanization and the speed of economic growth is not discussed.

Remember · Assumption questions: pick the unstated belief the argument relies on; reject 'only', 'every' and topics the passage never touches.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (d) Relation between climate change and migration is not yet properly understood.

The passage keeps pointing to what is unsettled: no consensus on who a climate refugee is, gaps in understanding how climate change drives migration, and doubt over who will protect such migrants. The rational inference is that the link between climate change and migration is not yet properly understood.

• ✗ (a) The passage does not predict that the world cannot cope; it points to gaps in recognition and protection.
• ✗ (b) Stopping climate change is not discussed; the passage is about the migrants and their status.
• ✗ (c) 'The most important reason' goes beyond the passage, which says only that climate change is 'likely' to force migration.
• ✓ (d) 'There are still gaps in understanding how climate change will work as the root cause of migration' — the relation is not yet properly understood.

Remember · When a passage keeps pointing to gaps, lack of consensus and open questions, the inference is about incomplete understanding.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (b) 2 only

The passage recommends botanical pesticides as a 'practical sustainable alternative' because they avoid the ecological imbalance caused by synthetic ones, so it assumes that sustainable farming aims at minimal ecological imbalance. It neither bans synthetic pesticides outright nor claims botanicals control pests better.

• ✗ 1. 'Never' is too strong; the passage criticises indiscriminate use and offers an alternative, but does not call for a total ban.
• ✓ 2. Botanicals count as a sustainable alternative because synthetics 'cause ecological imbalance' — this only makes sense if sustainability means limiting such imbalance.
• ✗ 3. Botanicals are described as safer and biodegradable, not as more effective at controlling pests.

Remember · Separate 'safer' from 'more effective', and 'should reduce' from 'should never' — assumptions that harden the passage's claims are invalid.

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Answer: (a) 1 only

Botanical pesticides are described as safer to the user, breaking down into harmless compounds and reducing human health hazards, so statement 1 fits. They break down within hours or days, so they are not persistent, and the passage never calls them essential for biodiversity.

• ✓ 1. They are 'safer to the user', break down into 'harmless compounds' and reduce 'human health hazards'.
• ✗ 2. The reverse: they break down within hours or days; it is synthetic pesticides that are persistent.
• ✗ 3. They 'help in the maintenance' of the diversity of predators; 'essential' for 'any ecosystem' is far stronger than the passage.

Remember · Watch for statements that transfer a property of one of the two things compared to the other — persistence belongs to synthetics here.

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Answer: (b) 4

If a number and its reverse are both multiples of 7, so is their difference, 99 × (first digit − last digit). Since 99 is not a multiple of 7, the first and last digits must differ by 7 — giving just 168, 861, 259 and 952.

1. Let the number be 100a + 10b + c; its reverse is 100c + 10b + a.
2. Their difference is 99(a − c). Both are multiples of 7 and 99 is not, so a − c must be a multiple of 7.
3. The digits are all different, so a − c = ±7: (a, c) = (1, 8), (8, 1), (2, 9), (9, 2) or (7, 0). The last fails: 7b0 is divisible by 7 only if b = 0 or 7, which repeats a digit.
4. Find the middle digit in each case: 1b8 → 168 = 7 × 24; 8b1 → 861 = 7 × 123; 2b9 → 259 = 7 × 37; 9b2 → 952 = 7 × 136.
5. Each case has exactly one suitable middle digit, so there are 4 such numbers.
6. Check: 861 and 952 are the reverses of 168 and 259, and all four have three different digits.

Remember · A 3-digit number and its reverse differ by 99 × (first − last digit); this turns 'both divisible by 7' into an end-digit condition.

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Answer: (d) 1 is false.

'Some colours are not pleasant' is the exact contradictory of 'All colours are pleasant', so if statement 4 is true, statement 1 must be false. Statements 2 and 3 could go either way.

1. Statement 4 (some colours are not pleasant) and statement 1 (all colours are pleasant) are contradictories: exactly one of them is true.
2. 4 is true, so 1 is false — definitely.
3. Statement 2 may or may not hold, because the remaining colours may or may not be pleasant; so 2 and 3 are both undetermined.
4. Only (d) is certain.

• ✗ (a) 1 is false, so '1 and 2 are true' cannot hold.
• ✗ (b) 4 does not rule out some colours being pleasant, so 3 is not certain.
• ✗ (c) 2 may still be true — some colours can be pleasant while others are not.
• ✓ (d) 'Some … are not' is the contradictory of 'All … are'; when one is true, the other is false.

Remember · Contradictory pairs: All vs Some-not, and No vs Some. If one of a pair is true, the other is false; other pairs stay undetermined.

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Answer: (c) 90

Numbers between 99 and 1000 are the 3-digit numbers 100 to 999. With 8 fixed in the units place, the hundreds digit has 9 choices and the tens digit 10 choices, giving 9 × 10 = 90.

1. Numbers strictly between 99 and 1000: 100 to 999.
2. Units digit fixed as 8.
3. Hundreds digit: 1–9 (9 ways); tens digit: 0–9 (10 ways).
4. Count = 9 × 10 = 90.
5. Check: 108, 118, …, 998 rise in steps of 10, so the count is (998 − 108) ÷ 10 + 1 = 90.

Remember · Fix the given digit, then multiply the free choices for the other places — the leading digit cannot be 0.

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Answer: (d) skewed to the left

In a skewed distribution the mean is pulled furthest towards the long tail, the mode sits at the peak, and the median lies between them. Mean < Median < Mode means the tail stretches to the left: the distribution is negatively skewed.

1. In a symmetric distribution mean = median = mode, so (a) and (c) are out.
2. A few very small values pull the mean down more than the median, while the mode (the peak) is least affected.
3. So mean < median < mode signals a long left tail: skewed to the left (negative skew).
4. Skewed to the right would give the reverse order: mode < median < mean.

Remember · The mean chases the tail: mean below median means left-skewed; mean above median means right-skewed.

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Answer: (b) 38

Next year's age is 2 more than last year's, so we need a square that is 2 less than a cube: 25 + 2 = 27. Mr. X was 25, is 26 now and turns 27 next year. The next cube is 64, which is 38 years away from his present age.

1. If last year's age is n² and next year's is m³, then m³ − n² = 2.
2. Try cubes: 8 − 2 = 6 (not a square), 27 − 2 = 25 = 5² ✓, 64 − 2 = 62, 125 − 2 = 123, 216 − 2 = 214 — only 27 works for a human age.
3. So he was 25 last year, is 26 now and will be 27 next year.
4. After 27, the next cube is 4³ = 64.
5. Years to wait from his present age: 64 − 26 = 38.

Remember · 'Square last year, cube next year' means the two numbers differ by 2 — list squares and cubes side by side.

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Answer: (a) 3: 1: 1

Working together for the same time, each person's share of the earnings follows his rate of work. With P = 3Q and P + Q = 4R, we get 4Q = 4R, so R = Q and the ratio is 3 : 1 : 1.

1. Let Q's rate be 1 unit a day; then P's rate = 3.
2. P + Q = 4 = 4 × R's rate, so R's rate = 1.
3. Working for the same time, their shares follow their rates: P : Q : R = 3 : 1 : 1.

Remember · When people work together for the same time, split the earnings in the ratio of their work rates.

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Answer: (b) A is the husband of D.

A, E and B are sons, so they are the three males, and C, D and F are the three females. D's son must be B, because A and E are F's sons; so D is B's mother and A is B's father. With only one married couple, A is D's husband.

1. A and E are sons of F, and B is the son of A — so A, B and E are males. Equal numbers means C, D and F are the three females.
2. D is the mother of a boy and a girl. Her boy cannot be A or E, whose mother is F, so it is B.
3. B's father is A and B's mother is D, so A and D are the only married couple.
4. D's girl is C; F, the mother of A, belongs to the older generation.
5. So A is the husband of D.

• ✗ (a) A and B are sons, so they are males.
• ✓ (b) A is B's father and D is B's mother; with only one married couple, A and D are husband and wife.
• ✗ (c) E is F's son, and F is A's mother, so neither is D's child.
• ✗ (d) F is the mother of A, D's husband, so F is D's mother-in-law, not her mother.

Remember · In family puzzles, fix genders first from 'son', 'mother' and similar words, then use 'only one married couple' to pair the parents.

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Answer: (b) 16

In the worst case you pick all 8 green and all 7 white balls first — 15 balls and still no red. The next ball must be red, so 16 balls guarantee at least one of each colour.

1. Worst case: the two largest colour groups come out first — 8 green + 7 white = 15 balls.
2. Only red balls remain, so the 16th ball is red.
3. 16 is enough in every case, and 15 is not (the all-green-and-white case), so the minimum is 16.

Remember · To be assured of one of each colour, take every ball except the smallest colour group, then add 1.

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Answer: (c) 12

There are 4! = 24 arrangements in all. Treating the two girls as one block gives 3! × 2 = 12 arrangements in which they sit together, so 24 − 12 = 12 keep the girls apart.

1. All arrangements of 4 different children: 4! = 24.
2. Girls together: treat them as one unit → 3 units → 3! = 6, and the girls can swap within the unit → 6 × 2 = 12.
3. Girls not together: 24 − 12 = 12.
4. Check (gap method): arrange the boys in 2! = 2 ways, leaving 3 gaps; place the two girls in 2 of the gaps in 3 × 2 = 6 ways; total 2 × 6 = 12.

Remember · 'Not together' = total − together; or seat the others first and put the separated people in the gaps.

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Answer: (a) 8

Only the small cubes that touch no outer face stay unpainted. Peeling a 1 cm layer off every side leaves a 2 × 2 × 2 core, so 8 small cubes have no painted face.

1. A 4 × 4 × 4 cube gives 64 small cubes.
2. Cubes with no painted face form the inner block: (4 − 2) × (4 − 2) × (4 − 2).
3. (4 − 2)³ = 2³ = 8.
4. Check: 8 corner cubes + 24 edge cubes + 24 face-centre cubes = 56 painted, and 56 + 8 = 64.

Remember · For an n × n × n painted cube, the unpainted small cubes number (n − 2)³.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (c) G is to the immediate right of D.

'Sixth to the left/right' in a row of eight forces the pairs A–E and C–H into places 1 & 7 and 2 & 8. F must stand next to E, which works only with A at 1 and E at 7. The row is A C B D G F E H, so G is to the immediate right of D.

1. Number the places 1–8 from left to right; facing North, a person's right is the higher number.
2. A is sixth to the left of E: (A, E) = (1, 7) or (2, 8). H is sixth to the right of C: (C, H) = (1, 7) or (2, 8). The two pairs must take different sets.
3. Case C = 1, H = 7, A = 2, E = 8: E's only neighbour is place 7 (H), so F cannot be next to E — rejected.
4. So A = 1, C = 2, E = 7, H = 8. F must be at 6 (next to E) and G at 5 (immediately left of F); G is not at an end.
5. B and D fill places 3 and 4; B is not next to G (5), so B = 3 and D = 4.
6. Row: A C B D G F E H. G (5) is immediately right of D (4).
7. Check the others: C is to the right of A, not the left; D's neighbours are B and G; A and E are at 1 and 7, not both ends.

Remember · In linear seating, 'k-th to the left' clues with a large k allow few places — list them first, then test the adjacency clues.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (b) 4

'Colour' is the only word in all three phrases and 5 the only digit in all three codes. 'Chalk' is shared by the first and third phrases, whose codes also share 2. That leaves 4 for 'white' in 254.

1. 'colour' is in all three phrases and 5 is in all three codes, so colour = 5.
2. 'chalk' is in 256 and 254; apart from 5 they share 2, so chalk = 2.
3. 254 = white colour chalk, so white = 4.
4. Check: 256 then gives red = 6, and 589 splits green and flower between 8 and 9.

Remember · In word-to-digit codes, match the word common to two phrases with the digit common to their codes, and eliminate step by step.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (c) Air quality index is not helpful to the residents of many of our large cities.

An AQI helps when pollution is usually low and only spikes now and then, so people can act on a warning. In many large Indian cities pollution stays in the danger zone for much of the year, so the index gives residents little they can act on.

• ✗ (a) Governments are not blamed; the passage is about how useful the index is.
• ✗ (b) 'Absolutely no need' is extreme, and 'our country' overgeneralises — the passage speaks of many large cities and says the AQI is useful in other conditions.
• ✓ (c) When the index stays 'Red/Dangerous' day after day, there is 'not much any one can do' — so it does not help residents of many large cities.
• ✗ (d) Public awareness is not the passage's concern; its point is that warnings lose value when pollution is always high.

Remember · Match the scope of the inference to the passage: 'many large cities' supports a limited claim, not 'the whole country' or 'every city'.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (c) We must create conditions for the faster growth of productive jobs outside of agriculture even while improving the productivity of agriculture.

Farm incomes can rise only if fewer people depend on agriculture, yet industry's new jobs are mostly low-productivity and productive service jobs are growing slowly. So India must create productive jobs outside agriculture while also raising incomes and productivity within it.

• ✗ (a) Too narrow: it looks only at service jobs, while the passage's concern covers agriculture and industry as well.
• ✗ (b) The passage says industry's jobs are largely low-productivity, so it does not call manufacturing 'highly productive'; simply shifting farm workers is also more drastic than anything it proposes.
• ✓ (c) People must move out of agriculture into productive jobs, and per capita farm incomes must rise — this option covers every part of the passage.
• ✗ (d) Hybrid and GM crops are not mentioned; the passage's concern is productive jobs.

Remember · When several options are partly right, choose the one that covers every sector or point the passage raises.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (a) Agricultural practices that enhance biodiversity can often increase farm output and reduce the vulnerability to disasters.

The examples show biodiversity-friendly farming cutting hurricane damage, raising income from pasture and coffee, improving pollination and making cattle farming more sustainable. The inference is that such practices can often raise output and reduce vulnerability to disasters.

• ✓ (a) Less hurricane damage (lower vulnerability) and higher incomes, better pollination and more sustainable cattle production (higher output) — all from practices that also add biodiversity.
• ✗ (b) The reverse of the passage, which favours ecoagriculture over conventional techniques.
• ✗ (c) The passage speaks of biodiversity outside protected areas; it does not propose ecoagriculture inside them.
• ✗ (d) 'Very high' yields is an overstatement; the passage reports reduced damage and higher incomes, not crop yields as such.

Remember · Prefer the cautious inference ('can often') that sums up all the examples over options that overstate or reverse them.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (c) India should push up the public investments and encourage the private investments in research and development, technology upgradation and skill development.

Indian manufacturing must move to higher-tech, higher-value and higher-productivity sectors, and the growing global markets are mainly in high-technology, capital-intensive goods. Getting there needs investment in research, technology upgradation and skills.

• ✗ (a) The passage says India must move up from these sectors; it does not credit India with high value added or productivity in them.
• ✗ (b) The passage treats the move to such manufacturing as necessary; nothing says it is impossible.
• ✓ (c) Capturing high-tech, capital-intensive markets calls for investment in research, technology and skills — the natural policy conclusion.
• ✗ (d) The passage says India 'needs to capture' these markets, which means it has not done so yet.

Remember · When a passage sets a challenge, the logical inference is usually the means to meet it, not a claim that it is already met.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (a) Increasing the efficiency of farm-to-fork value chain is necessary to reduce the poverty and malnutrition.

India produces record amounts of food and holds huge grain stocks, yet a quarter of the world's undernourished live here and many households spend about half their budget on food. The gap lies between the farm and the plate, so improving the farm-to-fork chain follows logically.

• ✓ (a) Full granaries alongside hunger point to a failure in moving food efficiently and affordably to people — the farm-to-fork chain.
• ✗ (b) Production is already at a record, yet malnutrition persists, so more output will not 'automatically' remove it.
• ✗ (c) The passage notes record production but does not say productivity is high enough to stop improving.
• ✗ (d) Welfare funding is not discussed, and 'will ultimately eliminate' is an overstatement.

Remember · A 'corollary' follows directly from the passage's contrast — plenty of food alongside hunger points to distribution, not production.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (b) A strong Centre is a binding force for national integrity.

The Centre is the thread that holds the States together as a necklace; if it snaps, they scatter. So a strong Centre is the binding force that keeps the nation integrated.

• ✗ (a) The analogy says nothing about the States' strength; it stresses the Centre as the thread that binds.
• ✓ (b) The thread (Centre) turns the pearls (States) into a necklace (the nation); without it they scatter — a strong Centre binds the nation.
• ✗ (c) The statement does not present the Centre as an obstacle to the States.
• ✗ (d) State autonomy is not the point of the analogy.

Remember · In analogy items, map each image to its meaning (thread = Centre, pearls = States) and choose the view that follows from that mapping.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (b) rule according to the consent of the governed

The speaker says every man, even the poorest, must first consent to a government before being bound by it, and is not bound by a government in which he had no voice. This argues for rule according to the consent of the governed.

• ✗ (a) The rich and the poor are mentioned only to say that both have a life to live; sharing out wealth is not proposed.
• ✓ (b) Every man 'ought first by his own consent to put himself under the government' — government must rest on the consent of the governed.
• ✗ (c) The speaker wants the poorest to have a voice, not to rule over others.
• ✗ (d) Taking property from the rich is not suggested anywhere.

Remember · Stay with the claim the speaker actually makes ('consent', 'voice'); options that go further, like rule of the poor, distort it.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (c) 0.80 inch

The six days total 6 × 0.50 = 3.00 inches and the first four days 4 × 0.40 = 1.60 inches, so the last two days had 1.40 inches. Split in the ratio 4 : 3, the fifth day had 1.40 × 4/7 = 0.80 inch.

1. Total for six days = 6 × 0.50 = 3.00 inches.
2. Total for the first four days = 4 × 0.40 = 1.60 inches.
3. Last two days = 3.00 − 1.60 = 1.40 inches.
4. Fifth day : sixth day = 4 : 3, so the fifth day = 1.40 × 4/7 = 0.80 inch.
5. Check: sixth day = 0.60 inch, and 1.60 + 0.80 + 0.60 = 3.00.

Remember · Turn averages into totals first, then split the remaining total in the given ratio.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (a) B

Once the direct clues are placed, History, Geography and Mathematics are left for B, D and E. Clue 4 rules out History and Mathematics for B, so B is the Geography lecturer (and hence the one from Kanpur).

1. Direct clues: C – Delhi – Sociology; D – Shillong; F – Srinagar – Commerce; G – Chennai – Statistics; A – Economics.
2. Cities left for A, B and E: Hyderabad, Kanpur, Mumbai. A is not from Hyderabad (clue 5), and Kanpur's lecturer teaches Geography while A teaches Economics — so A is from Mumbai.
3. Subjects left for B, D and E: History, Geography, Mathematics. B teaches neither History nor Mathematics (clue 4), so B teaches Geography.
4. Geography goes with Kanpur (clue 1), so B is from Kanpur, and the last city, Hyderabad, goes to E.
5. D and E share History and Mathematics in some order — the data do not decide which.
6. Geography: B.

Remember · In matching grids, place every direct clue first, then use 'neither/nor' and 'does not' clues to eliminate; the last blanks fall into place.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (b) Mumbai

The Economics lecturer is A. Only Hyderabad, Kanpur and Mumbai are free; clue 5 rules out Hyderabad, and Kanpur's lecturer teaches Geography, so A must be from Mumbai.

1. Direct clues: C – Delhi – Sociology; D – Shillong; F – Srinagar – Commerce; G – Chennai – Statistics; A – Economics.
2. Cities left for A, B and E: Hyderabad, Kanpur, Mumbai. A is not from Hyderabad (clue 5), and Kanpur's lecturer teaches Geography while A teaches Economics — so A is from Mumbai.
3. Subjects left for B, D and E: History, Geography, Mathematics. B teaches neither History nor Mathematics (clue 4), so B teaches Geography.
4. Geography goes with Kanpur (clue 1), so B is from Kanpur, and the last city, Hyderabad, goes to E.
5. D and E share History and Mathematics in some order — the data do not decide which.
6. Economics is A's subject, and A is from Mumbai.

Remember · When a city is tied to a subject (Kanpur–Geography), anyone with a different subject is ruled out of that city at once.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (b) E

A (Economics) must be from Mumbai, and B, the Geography lecturer, must be from Kanpur. The only city left, Hyderabad, therefore belongs to E.

1. Direct clues: C – Delhi – Sociology; D – Shillong; F – Srinagar – Commerce; G – Chennai – Statistics; A – Economics.
2. Cities left for A, B and E: Hyderabad, Kanpur, Mumbai. A is not from Hyderabad (clue 5), and Kanpur's lecturer teaches Geography while A teaches Economics — so A is from Mumbai.
3. Subjects left for B, D and E: History, Geography, Mathematics. B teaches neither History nor Mathematics (clue 4), so B teaches Geography.
4. Geography goes with Kanpur (clue 1), so B is from Kanpur, and the last city, Hyderabad, goes to E.
5. D and E share History and Mathematics in some order — the data do not decide which.
6. Hyderabad: E.

Remember · Solve the whole grid once; later questions on the same set then take seconds.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (b) B

Collect each teacher's subjects, counting a repeated subject once. B teaches Hindi, English, Geography, History and French — five subjects. A teaches three, and C, D and E teach two each.

1. A: Hindi, English (with B) and Mathematics, Hindi (with D) → Hindi, English, Mathematics = 3.
2. B: Hindi, English; English, Geography; History, French → Hindi, English, Geography, History, French = 5.
3. C: English, Geography = 2. D: Mathematics, Hindi = 2. E: History, French = 2.
4. B teaches the most subjects.

Remember · List each person's subjects as a set, counting a subject once even if it appears in two statements.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (d) 45

A number and its reverse differ by 9 × (difference of the digits). When the larger is less than twice the smaller, the quotient is 1 and the remainder is that difference; the biggest such case is 94 ÷ 49, which leaves 45.

1. Let the larger number be 10a + b and the smaller 10b + a, with a > b.
2. Their difference is 9(a − b). If the larger is less than twice the smaller, the quotient is 1 and the remainder is exactly 9(a − b).
3. Quotient 1 needs 10a + b < 2(10b + a), i.e. 8a < 19b. With a = 9 this needs b ≥ 4, so the best pair is 94 and 49: remainder 9 × 5 = 45.
4. If the quotient is 2 or more, then 8a ≥ 19b forces b ≤ 3, so the smaller number is at most 39 and the remainder is less than 39.
5. Largest possible remainder = 45 (94 = 1 × 49 + 45).

Remember · A number and its reverse differ by 9 × (difference of digits); when the quotient is 1, that difference is the remainder.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (b) ₹ 42,000

Let incomes be 4k and 3k and expenses 3m and 2m. Equal savings give 4k − 3m = 3k − 2m, so k = m, and then 4k − 3k = ₹6,000 gives k = ₹6,000. Total income = 7k = ₹42,000.

1. Incomes: 4k and 3k; expenses: 3m and 2m.
2. Savings: 4k − 3m = 6000 and 3k − 2m = 6000.
3. Subtracting: k − m = 0, so m = k. Then 4k − 3k = k = 6000.
4. Total income = 4k + 3k = 7 × 6000 = ₹42,000.
5. Check: X earns ₹24,000 and spends ₹18,000; Y earns ₹18,000 and spends ₹12,000 — each saves ₹6,000.

Remember · When both save the same amount, equate the two savings expressions first — it links the two ratio multipliers.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (a) 4

Take P as the corner where the three perpendicular surfaces meet. The fly's distances from the two walls and the ceiling are its three coordinates, so 1² + 8² + h² = 9², giving h² = 16 and h = 4 m.

1. Take P as the origin, with the two walls and the ceiling as three mutually perpendicular planes.
2. The distance from each plane is one coordinate: 1 m, 8 m and h m (from the ceiling).
3. Distance from P: √(1² + 8² + h²) = 9, so 1 + 64 + h² = 81.
4. h² = 16, so h = 4 m.

Remember · Distance from a corner = √(x² + y² + z²), where x, y and z are the distances from the three faces meeting there.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (b) E

From C the only exit is to A, and from A the only onward move is to E, so every journey from C to H has to pass through E. G and F lie only on the longer of the two routes, so they are not compulsory.

1. Exits from each station: A → E; B → F, G; C → A; D → H, F, E; E → G, C, A, D; F → D; G → C, B; H → G.
2. From C the only move is to A, and from A the only move is to E — so E is on every route out of C.
3. Routes to H: C → A → E → D → H, or C → A → E → G → B → F → D → H; both pass through E.
4. G and F appear only on the longer route, so they are not compulsory; E is the station UPSC's key accepts.

Remember · For 'must pass through', trace the forced moves from the start: a station with a single exit forces the next station onto every route.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 1 Oct 2026 (how we verify). Permalink · Report an error

Answer: (d) 4

From F the only exit is D, and from D the train can go to E or H. Through E it reaches A directly, via C, or via G and C (3 routes); through H it must go to G, then C, then A (1 route). That makes 4 routes.

1. Exits from each station: A → E; B → F, G; C → A; D → H, F, E; E → G, C, A, D; F → D; G → C, B; H → G.
2. F's only exit is D.
3. D → E: then E → A (F-D-E-A), E → C → A (F-D-E-C-A), or E → G → C → A (F-D-E-G-C-A). E → G → B leads only back to F or G, already used.
4. D → H: H → G, then G → C → A (F-D-H-G-C-A); G → B leads back to F — a dead end.
5. Total routes without repeating a station = 3 + 1 = 4.

Remember · Count routes with a tree: branch at every station and prune any branch that revisits a station or reaches a dead end.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (c) A

H's only exit is G, and with G to C closed, G must go to B, then F, then D. From D the train reaches C only through E. The route H-G-B-F-D-E-C passes E, D and B but never needs A.

1. Exits from each station: A → E; B → F, G; C → A; D → H, F, E; E → G, C, A, D; F → D; G → C, B; H → G.
2. H → G is the only exit from H.
3. G → C is closed, so G → B; then B → F (B → G goes back) and F → D.
4. From D: D → H goes back, so D → E; from E go straight to C.
5. Route: H → G → B → F → D → E → C. It passes E, D and B but not A.
6. A can be entered only from C or E and leads only back to E, so it is never needed.

Remember · When a link closes, trace the forced path one exit at a time; stations off that path need not be passed.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (d) None of the above

A 2-digit number and its reverse differ by 9 × (difference of the digits), so the digits must differ by 3. That gives 41, 52, 63, 74, 85, 96 and 14, 25, 36, 47, 58, 69 (and 30, if 03 is allowed) — at least 12 numbers, far more than 3, 4 or 5.

1. (10a + b) − (10b + a) = 9(a − b), which is 27 in size when the digits differ by 3.
2. Tens digit 3 more than units: 41, 52, 63, 74, 85, 96 (and 30, if its reverse 03 = 3 is accepted).
3. Tens digit 3 less than units: 14, 25, 36, 47, 58, 69.
4. That is 12 numbers (13 counting 30); even one direction alone gives 6. None of 3, 4 or 5 fits.

Remember · Number − reverse = 9 × (digit difference). Divide the given difference by 9 to get the digit gap, then list the pairs.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (b) 342

Pages 1–9 use 9 digits, pages 10–99 use 90 × 2 = 180 digits, and pages 100–150 use 51 × 3 = 153 digits. The total is 342.

1. Pages 1–9: 9 pages × 1 digit = 9.
2. Pages 10–99: 90 pages × 2 digits = 180.
3. Pages 100–150: 51 pages × 3 digits = 153.
4. Total = 9 + 180 + 153 = 342.

Remember · Count digits band by band: pages in a band = last − first + 1, times the digits on each page.

Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error