Fact 1: Pesticides can cause pollution.

Fact 2: Pollution is the release of harmful substances into the environment.

Given the two facts above, answer the question "Which of the following can release harmful substances into the environment?" with the following options: 
- vehicles
 - cigarettes
 - fossil fuels
 - Thunderstorms
 - Photosynthesis
 - Pesicides
 - Tree sap
 - mines


 

      Pesicides   