UPSC Prelims 2019 · CSAT
Question 66: Reading Comprehension
On the basis of the above passage, the following assumptions have been made :
- 1.Global warming is a frequently occurring natural phenomenon.
- 2.The impending global warming will not adversely affect small mammals.
- 3.Humans are responsible for the loss of the Earth's natural resilience.
Which of the above assumptions is/are valid ?
AnswerUPSC’s answer is (b).
The passage says the small-mammal community stayed stable and resilient during a warming episode about 13,000 years ago, but human-made changes since the late nineteenth century cut biomass and energy flow, so ecosystems now adapt less easily. Humans are therefore responsible for the loss of resilience (3). Warming is not shown to be frequent (1), and small mammals are shown to be doing worse under present conditions, so 2 is contradicted.
- 1. Only one past warming episode is mentioned, not frequent ones.
- 2. Ecosystems now adapt poorly, so harm to small mammals is more likely, not ruled out.
- 3. Human-made changes caused the drop in biomass and energy flow.
How you could have got this
- If you were sure statement 2 is not correct, (a), (c) and (d) go: each of them includes 2.
What you needed to know: Ecosystems now adapt poorly, so harm to small mammals is more likely, not ruled out.
Only (b) is left. You didn’t need statements 1 or 3.
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) Wrong: 1 and 2 are both unsupported.
- (b) Right: only the human role in lost resilience is stated.
- (c) Wrong: 2 runs against the passage.
- (d) Wrong: 1 and 2 are unsupported.
Answer: UPSC’s key. Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2019, General Studies Paper II (CSAT), Series A. The paper on upsc.gov.in.