Which statement about DNA viruses is true?

• A. DNA viruses replicate in the nucleus using host or viral DNA polymerases.
• B. DNA viruses replicate in the cytoplasm using RNA polymerase.
• C. DNA viruses replicate in mitochondria using reverse transcriptase.
• D. DNA viruses do not require any polymerases.

Answer: (A)

DNA viruses copy their genomes with DNA polymerases, and they do so mainly in the nucleus where the host cell’s replication machinery is located, with some viruses also carrying their own viral DNA polymerase. This is why the statement that DNA viruses replicate in the nucleus using host or viral DNA polymerases is correct. DNA synthesis requires a DNA-dependent polymerase, not RNA polymerase, and replication in mitochondria isn’t how these viruses operate. There are exceptions like certain large DNA viruses that replicate in the cytoplasm and carry their own polymerases, but the general principle described fits the typical DNA virus replication process.