Fact 1: Viruses infect and live inside the cells of living organisms.

Fact 2: Influenza viruses mutate.

Given the two facts above, answer the question "What can infect and live inside the cells of living organisms?" with the following options: 
- Leptospirosis
 - fish
 - spiders
 - Pesticides
 - influenza
 - horses
 - insects
 - bacteria


 

     influenza    