Fact 1: Scraping oneself on a contaminated object may cause infection.

Fact 2: An infection is an invasion of the body by bacteria.

Given the two facts above, answer the question "Scraping oneself on an object that is what, may cause an invasion of the body by bacteria?" with the following options: 
- unknown
 - safe
 - threatened
 - harmful substances
 - Pollution
 - foreign
 - barrel-shaped
 - contaminated


 

        contaminated 