Which of the following bases are present both in $DNA$ and $RNA$?

Given below are two statements:
Statement $I$: Cytosine and guanine are formed in equal quantities in $DNA$ hydrolysis.
Statement $II$: Adenine and uracil are formed in equal quantities in $RNA$ hydrolysis.
The correct answer is:

Which of the following is not a protein?

In both $DNA$ and $RNA$,the heterocyclic base and phosphate ester linkage are present at which positions of the sugar respectively?

Identify the nitrogen atom of a purine base that bonds with the $1^{\prime}$ carbon of ribose to form a ribonucleoside.

How are nucleotides linked together in nucleic acids?