Which of the following bases is present in $RNA$ instead of $Thymine$ found in $DNA$?

The modern concept of gene is

Which of the following nitrogen bases is found only in $DNA$?

What is the full form of $DNA$?

Exposure of an organism to $UV$ radiation causes:

Thirty percent of the bases in a sample of $DNA$ extracted from eukaryotic cells is adenine. What percentage of cytosine is present in this $DNA$ (in $\%$)?