Which of the following nucleotides is only found in RNA?

A.

Guanine

B.

Thymine

C.

Uracil

D.

Adenine

The correct answer is:

C. Uracil

Explanation: Uracil is a nucleotide base found exclusively in RNA, where it replaces thymine, which is found in DNA. The four nucleotides in RNA are adenine, cytosine, guanine, and uracil.

• A. Guanine is present in both RNA and DNA.
• B. Thymine is found only in DNA, not in RNA.
• D. Adenine is present in both RNA and DNA.