The products of complete hydrolysis of DNA are
(A) phosphoric acid.
(B) N-containing heterocyclic compound.
(C) nitrogen gas
(D) pentose sugar.
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → (A), (B) and (D) only
DNA is a polymer of nucleotides, each made of a pentose sugar, a nitrogenous base and a phosphate group; complete hydrolysis breaks all the links and releases these three kinds of units.
(A) phosphoric acid. — Correct. The phosphate groups are released as phosphoric acid.
(B) N-containing heterocyclic compound. — Correct. The bases A, G, C and T are nitrogen-containing heterocyclic compounds (purines and pyrimidines).
(C) nitrogen gas — Incorrect. Hydrolysis only breaks bonds by adding water; the nitrogen stays inside the bases and no \( \ce{N2} \) is released.
(D) pentose sugar. — Correct. The sugar 2-deoxyribose is a pentose.
NCERT (2026-27 edition):
Chemical Composition of Nucleic Acids
