Test yourself

Curiosity

Class 7 · Science & Environment

Ch 2 · Exploring Substances: Acidic, Basic, and Neutral

Real UPSC Prelims questions from 2016–2026, linked to this book. Try each one first, then open the answer. 2026 answers follow UPSC's provisional answer key.

Prelims 2021 · Q20

In the nature, which of the following is/are most likely to be found surviving on a surface without soil?

1.Fern
2.Lichen
3.Moss
4.Mushroom

Select the correct answer using the code given below.

(a)1 and 4 only
(b)2 only
(c)2 and 3
(d)1, 3 and 4

Show answer

UPSC's answer: (c)

NCERT answers it: Class 11 Fundamentals of Physical Geography, Ch 5 (Geomorphic Processes); Class 7 Curiosity, Ch 2 (Exploring Substances: Acidic, Basic, and Neutral).

Class 11 Fundamentals of Physical Geography, ch 5: bare weathered rock is first colonised by bacteria, mosses and lichens, before soil forms. Class 7 Curiosity, ch 2: lichens grow on rocks and trees. So 2 and 3. Answer (c).

Hindi version: UPSC's official question paper (2021), question 20 ↗

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