UPSC CSE Prelims
Question 3
Consider the following techniques/phenomena:
- Budding and grafting in fruit plants
- Cytoplasmic male sterility
- Gene silencing
Which of the above is/are used to create transgenic crops?
View correct answer and explanation
Correct answer: B
Correct Option: B
Explanation: The supplied key identifies cytoplasmic male sterility and gene silencing as techniques associated with genetically engineered crop development; ordinary grafting is vegetative propagation.
Statement/Pair-wise Analysis:
Statement/Item 1: Incorrect - Budding or grafting joins existing plant tissues; it does not insert engineered DNA.
Statement/Item 2: Correct - Cytoplasmic male sterility can facilitate hybrid-seed production in transgenic-crop programmes.
Statement/Item 3: Correct - Gene silencing, including engineered RNA interference, can alter gene expression in crops.
Option-wise Analysis:
A: Incorrect - includes incorrect statement/item 1; omits correct statement/items 2, 3.
B: Correct - includes all and only the correct items.
C: Incorrect - includes incorrect statement/item 1; omits correct statement/item 2.
D: Incorrect - omits correct statement/items 2, 3.
Review Note: Cytoplasmic male sterility can also arise naturally and is used in non-transgenic hybrids; it is not intrinsically a transgenic method. Keep the exam-key framing distinct from the biological definition.