Fact 1: Viruses are usually considered to be nonliving.

Fact 2: Viruses Viruses are the smallest agents of disease.

Given the two facts above, answer the question "What are usually considered to be nonliving?" with the following options: 
- direct damage to the lungs
 - bacteria
 - harmful substances
 - major threat to health
 - humans
 - the smallest agents of disease
 - starfish
 - Contaminated wounds


 

      the smallest agents of disease   