32p can be used to make any nucleotide (a, c, g, or t) radioactive. which of the following explains why this is true?

The answer is: All nucleotides have a phosphorus atom that can be replaced with 32P.

DNA building blocks are nucleotides. Nucleotides contain a nitrogenous base, a five-carbon sugar, and, at least, one phosphate group. Exactly that phosphate group in the nucleotide has the phosphorus atom. Therefore, the phosphorus atom in the nucleotide can be replaced with radioactive phosphorus-32 (32P). This replacement has a wide use in labeling nucleic acids and thereby visualizing the target molecule.