You are presented with the question "Many _ can cause the immune system to not work properly." and the following answer choices: 
- fever
 - bacteria
 - radiation
 - fungi
 - A drug.
 - Allergies
 - cancers
 - Toxicity

Now knowing that immunodeficiency occurs when the immune system is not working properly and many cancers can cause immunodeficiency, choose the best answer.


 

       cancers  