Which of the following contributes to the double helical structure of $DNA$?

The base present in $DNA$,but not in $RNA$ is

Given below are two statements:
Statement $I$: $A$ unit formed by the attachment of a base to $1'-$position of sugar is known as nucleoside.
Statement $II$: When nucleoside is linked to phosphorous acid at $5'-$position of sugar moiety,we get nucleotide.
In the light of the above statements,choose the correct answer from the options given below:

Which base is present in $RNA$ but not in $DNA$?

The segment of $DNA$ which acts as the instrumental manual for the synthesis of the protein is

The total number of correct statements regarding the nucleic acids is..............
$A$. $RNA$ is regarded as the reserve of genetic information.
$B$. $DNA$ molecule self-duplicates during cell division.
$C$. $DNA$ synthesizes proteins in the cell.
$D$. The message for the synthesis of particular proteins is present in $DNA$.
$E$. Identical $DNA$ strands are transferred to daughter cells.