Answer:
The correct answer is option C.
Explanation:
The biosynthesis of the pyrimidines are the simple than the biosynthesis of the purines nucleotide as pyrimidines are synthesized rings first and added later to the ribose sugar.
The synthesis of the bases of the purines are synthesizes the ribose sugar is bind first and latter it is added to the purine ring which is ribose - 5- phosphate.
Thus, the correct answer is option C.