Which of the following nitrogen bases is NOT part of DNA?

Uracil is not a component of DNA; instead, it is a nitrogenous base found in RNA. In the structure of DNA, the nitrogenous bases include adenine, cytosine, guanine, and thymine. Adenine pairs with thymine, and cytosine pairs with guanine in the DNA double helix. In contrast, RNA utilizes uracil in place of thymine, pairing adenine with uracil instead. This distinction between DNA and RNA is fundamental in biochemistry, emphasizing the unique roles and structures of these two types of nucleic acids.