Which three nitrogenous bases are found in both DNA and RNA?

• A. Adenine, cytosine, and guanine
• B. Guanine, thymine, and uracil
• C. Adenine, thymine, and uracil
• D. Cytosine, thymine, and uracil

Answer: (A)

Verified step by step guidance

1. Recall that DNA and RNA are both nucleic acids composed of nitrogenous bases attached to a sugar-phosphate backbone.
2. Identify the four nitrogenous bases found in DNA: adenine (A), thymine (T), cytosine (C), and guanine (G).
3. Identify the four nitrogenous bases found in RNA: adenine (A), uracil (U), cytosine (C), and guanine (G).
4. Compare the bases in DNA and RNA to find which three are common to both molecules.
5. Conclude that adenine, cytosine, and guanine are the three nitrogenous bases found in both DNA and RNA.