You are presented with the question "What can infect and live inside the cells of living organisms?" and the following answer choices: 
- Leptospirosis
 - fish
 - spiders
 - Pesticides
 - influenza
 - horses
 - insects
 - bacteria

Now knowing that viruses infect and live inside the cells of living organisms and influenza viruses mutate, choose the best answer.


 

     influenza    