Viruses are usually considered to be nonliving, and variola major, the virus that causes smallpox, is considered a potential bioterrorism agent. Given these facts, many believe the cause of smallpox to be what among the following options:
- fever
 - negative
 - contamination
 - Allergies
 - Nonliving
 - heat or cold
 - dangerous
 - Leptospirosis


 

     Nonliving    