MCQ
For two statements are given$-$one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below.
Assertion: $\text{B-DNA}$ has a constant diameter of $20 A.$
Reason: A pyrimidine always pairs with a purine.
  • Both assertion and reason are true, and reason is the correct explanation of assertion.
  • B
    Both assertion and reason are true, but reason is not the correct explanation of assertion.
  • C
    Assertion is true, but reason is false.
  • D
    Both assertion and reason are false.

Answer

Correct option: A.
Both assertion and reason are true, and reason is the correct explanation of assertion.

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