Which is Not a Pyrimidine

Question

Which is not a pyrimidine?
A)adenine
B)thymine
C)cytosine
D)uracil
E)cytosine and thymine

Accepted Answer

Adenine is a purine, not a pyrimidine. The other answer choices - thymine, cytosine, and uracil - are all pyrimidines. Option E is incorrect because it includes two pyrimidines (cytosine and thymine) rather than excluding one.