UPSC Prelims 2020 · CSAT
Question 64: Reading Comprehension
With reference to the above passage, the following assumptions have been made :
- 1.Genome editing does not require the transfer of genes from one plant to another.
- 2.Through genome editing, the chosen genes can be altered precisely in a manner akin to the natural process that helps plants to adapt to the environmental factors.
Which of the above assumptions is/are valid?
AnswerUPSC’s answer is (c).
The passage separates genome editing from genome modification. Editing finds the part of a plant's own genome to change and repairs it with molecular scissors, copying what plants do naturally under attack, so it does not rely on moving genes between plants (1). The chosen genes can be altered very precisely through this speeded-up natural process (2). Both assumptions are valid.
- 1. Editing alters a plant's own genes and is contrasted with modification, so no gene transfer is needed.
- 2. The passage says the relevant genes can be altered very precisely, speeding up a natural process.
How you could have got this
- If you were sure statement 1 is correct, (b) and (d) go: each of them leaves 1 out.
What you needed to know: Editing alters a plant's own genes and is contrasted with modification, so no gene transfer is needed.
- Then, if you were sure statement 2 is correct, (a) goes: it leaves 2 out.
What you needed to know: The passage says the relevant genes can be altered very precisely, speeding up a natural process.
Only (c) is left. This one needs every statement.
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) 1 is valid, but 2 is also valid.
- (b) 2 is valid, but 1 is also valid.
- (c) Right: both are supported.
- (d) Both are supported, so saying neither is valid is wrong.
Answer: UPSC’s key. Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2020, General Studies Paper II (CSAT), Series A. The paper on upsc.gov.in.