UPSC Prelims 2006 · General Studies
Question 147: Science and Technology
Consider the following statements:
- 1.ELISA test is employed as the first and most basic test for an individual to detect cancer.
- 2.Almost 50% of human beings have Rh+ blood while the remaining have Rh- blood.
Which of the statements given above is/are correct?
AnswerThe answer is (d).
ELISA detects antibodies or antigens and is best known as a first screening test for HIV; it is not the first and basic test for cancer. About 85 per cent of people are Rh-positive and about 15 per cent are Rh-negative, not half and half. So neither statement is correct.
- 1. ELISA is a screening test best known for HIV, not a basic cancer test.
- 2. About 85 per cent of people are Rh-positive.
How you could have got this
- If you were sure statement 1 is not correct, (a) and (c) go: each of them includes 1.
What you needed to know: ELISA is a screening test best known for HIV, not a basic cancer test.
- Then, if you were sure statement 2 is not correct, (b) goes: it includes 2.
What you needed to know: About 85 per cent of people are Rh-positive.
Only (d) is left. This one needs every statement.
This follows an unofficial answer: UPSC has not published its key for this year, and if that answer is wrong, so is this path.
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) ELISA is not the first test for cancer.
- (b) Rh-positive people are about 85 per cent.
- (c) Both statements are false.
- (d) Correct: neither statement holds.
Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2006, General Studies. UPSC's own paper isn't online; the words are from a published compilation. The paper on upsc.gov.in.