The enzyme reverse transcriptase (RT) is found in Choose one: A. some DNA and some RNA viruses. B. some DNA viruses. C. all viruses. D. some RNA viruses.

The correct answer is D. some RNA viruses.

Explanation:

The enzyme reverse transcriptase (RT) is found in some retroviruses, such as HIV. It is a DNA polymerase, which converts the single stranded RNA of the virus into a double stranded DNA (retrotranscription process).