Which one of the following is the most logical and rational inference that can be made from the above passage?
Answer & explanation
Answer: (c) Sometimes, the campaigns against foreign plants are pointless.
Most invasive species are neither very successful nor very harmful; new arrivals usually raise diversity and often drive no native species extinct. So campaigns against foreign plants are sometimes pointless — 'sometimes' keeps the claim within what the passage shows.
- ✗ (a) Invaders are said to colonise disturbed habitats; the passage does not recommend using them to restore deserts or wastelands.
- ✗ (b) 'Most' and 'in many cases' leave room for harmful invaders; declaring all such laws unnecessary goes too far.
- ✓ (c) If most invaders do little harm, some campaigns against them achieve nothing; 'sometimes' fits the passage's hedged claims.
- ✗ (d) Higher diversity is a side-effect of arrivals; the passage does not advise introducing foreign plants on purpose.
Remember · Match qualifiers: 'most' and 'in many cases' in the passage support 'sometimes', not 'unnecessary' or a new policy.
Question and answer: UPSC's official GS Paper II (2019, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). ·