MCQ
In $DNA$, the complementary bases are
  • A
    Uracil and adenine; cytosine and guanine
  • Adenine and thymine; guanine and cytosine
  • C
    Adenine and thymine; guanine and uracil
  • D
    Adenine and guanine; thymine and cytosine

Answer

Correct option: B.
Adenine and thymine; guanine and cytosine
b
(b) $\mathop {{\rm{Adenine}} = {\rm{Thymine}}}\limits_{{\rm{2 hydrogen bonds}}} {\rm{,}}\,\mathop {{\rm{Guanine}} \equiv {\rm{Cytosine}}}\limits_{{\rm{3 hydrogen bonds}}} $

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