UPSC CIVIL SERVICES PRELIMINARY EXAMINATION
UPSC Prelims 2011— Question 45
Q45
Question
At present, scientists can determine the arrangement or relative positions of genes of DNA sequences on a chromosome. How does this knowledge benefit us? 1. It is possible to know the pedigree of livestock. 2. It is possible to understand the causes of all human diseases. 3. It is possible to develop disease-resistant animal breeds. Which of the statements given above is/are correct?
AnswerOption C
Explanation
Concept and answer: Option C is correct. Gene mapping supports livestock pedigree identification and disease-resistant breeding, but cannot explain all human diseases. The question should be approached by identifying the exact proposition being tested and then checking each alternative against that proposition. A familiar word or related fact is not enough; the option must be completely consistent with the underlying concept. Statement 1 is correct under the verified interpretation. Statement 2 is incorrect under the verified interpretation. Statement 3 is correct under the verified interpretation. Option A: Incorrect. It omits true statement(s) 3; includes false statement(s) 2. Option B: Incorrect. It omits true statement(s) 1, 3; includes false statement(s) 2. Option C: Correct. It selects exactly the valid statement combination and therefore matches the factual and logical requirements of the question. Option D: Incorrect. It includes false statement(s) 2. Exam takeaway: the decisive distinction is the one stated in the core explanation. Option C is the only choice that remains fully consistent with that distinction. This approach is useful for Prelims because many distractors contain a partially true statement but add an incorrect qualifier, reverse a relationship, confuse two institutions, or use an absolute term. Always test the entire option rather than recognizing only one familiar phrase.
Question Classification
SubjectScience & Technology
TopicBiology
SubtopicGenetics
Question TypeStatement-based MCQ
Difficultydifficult
VerificationVerified