In his experiments on the chemistry of $DNA$, Chargaff estimated the base composition of human sperms and found that Adenine constituted $31\%$ and Guanine $19\%$. The quantity of Cytosine in the $DNA$ of human somatic cell is likely to be

• A

  $31\%$

• B

  $19\%$

• C

  $38\%$

• D

  $68\%$