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).

this is math not biology xd

nucleic acid molecules are incredibly complex, containing the code that guarantees the four different nucleotide units comprise dna, the nucleic acid of interest to the genealogist. and one of four nitrogen-containing molecules called nucleotides