The correct answer is D. Uracil
Explanation
DNA is made up of different nucleotides made up of deoxyribose, a nitrogenous base that can be adenine, thymine, cytosine, or guanine, and a phosphate group. On the other hand, RNA is composed of a single chain of ribonucleotides, each of them formed by ribose, a phosphate, and nitrogenous bases adenine, guanine, cytosine, or uracil. RNA differs from DNA because instead of thymine it has uracil nitrogenous bases. According to the above, the correct answer is D. Uracil.
