2012 CSAT, all questions

UPSC Prelims 2012 · CSAT

Question 31: Reading Comprehension

Passage – 1 · as printed by UPSC
Passage beginning “Invasions of exotic species into new…”Passage beginning “Invasions of exotic species into new…”

How have the human beings influenced the biodiversity ?

  1. 1.By smuggling live organisms.
  2. 2.By building highways.
  3. 3.By making ecosystems sensitive so that new species are not allowed.
  4. 4.By ensuring that new species do not have major impact on local species.

Which of the statements given above are correct ?

a1 and 2
b2 and 3
c1 and 3
d2 and 4

AnswerUPSC’s answer is (a).

As the passage describes it, human influence on biodiversity runs through introductions of exotic species. Some are accidental results of transport, some are deliberate but illegal and for private gain, which covers smuggling live organisms (statement 1), and human transport links such as highways have breached the barriers that limit dispersal (statement 2). Statements 3 and 4 describe humans preventing new species or limiting their impact, which the passage does not say happens.

  • 1. Illegal introduction for private purposes, such as smuggling live organisms, is a named human route.
  • 2. Human transport links such as highways breach the barriers that limit species' spread.
  • 3. Humans are not described as making ecosystems resist new species.
  • 4. The passage says some introductions have major effects; it does not say humans ensure they do not.

How you could have got this

  1. If you were sure statement 1 is correct, (b) and (d) go: each of them leaves 1 out.

    What you needed to know: Illegal introduction for private purposes, such as smuggling live organisms, is a named human route.

  2. Then, if you were sure statement 2 is correct, (c) goes: it leaves 2 out.

    What you needed to know: Human transport links such as highways breach the barriers that limit species' spread.

Only (a) is left. You didn’t need statements 3 or 4.

Which options go is worked out from UPSC’s key and the options, not by a model.

Why each option is right or wrong
  • (a) Right. Smuggling and transport links both carry species across natural barriers.
  • (b) Wrong. Statement 3 is not in the passage.
  • (c) Wrong. Statement 3 is not in the passage, and this leaves out statement 2.
  • (d) Wrong. Statement 4 is not in the passage.

Answer: UPSC’s key. Explanation: written by UPSC Grade, not by UPSC.

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Source: UPSC, Civil Services (Preliminary) Examination 2012, General Studies Paper II (CSAT), Series A. The paper on upsc.gov.in.