Inject DNA or RNA into the nucleus of a cell to reproduce.

a. viruses

b. bacteria

c. viruses and bacteria

The answer is A, Viruses

Viruses cannot reproduce on their own, so they have to inject their DNA or RNA into the nucleuus of a cell. By doing this, the virus will take over that cells and within times, that cells will pop up and producing more viruses.

This reproduced virus will repeat the same process until our immune systems stop them