You are presented with the question "What can cause an uncontrolled growth and spread of abnormal cells?" and the following answer choices: 
- smoking cigarettes
 - some foods
 - Pesticides
 - cigarettes
 - smoking
 - some religions
 - some viruses
 - some books

Now knowing that some viruses can cause cancer and cancer is an uncontrolled growth and spread of abnormal cells, choose the best answer.


 

       some viruses  