Final answer:
The three nucleotides DNA and RNA share are Adenine, Cytosine, and Guanine. Thymine is unique to DNA, while Uracil is unique to RNA.
Step-by-step explanation:
The three nucleotides that DNA and RNA have in common are Adenine (A), Cytosine (C), and Guanine (G). These are the nitrogenous bases present in both DNA and RNA. In DNA, adenine pairs with thymine (T) and cytosine pairs with guanine. Alternatively, in RNA, adenine pairs with uracil (U). Thus, the correct answer is D) Adenine, Cytosine, Guanine.