Amino acid

Nitrogen is derived from the breakdown of?
a)Amino acids
b)Cholesterol
c)Glucose
d)Purines
e)Pyrimidines
I know the answer is A but could it not also be purines as its breakdown creates uric acid and that has nitrogen in it? Or am I misinterpreting the question

You're correct that breakdown of purines produces uric acid which contains nitrogen, however uric acid isn't a source of nitrogen. The term "derived from" usually refers to the direct source of nitrogen in the body, thus used for metabolic activity in the cells, rather than a waste product. So the answer is just A, as you said.