Fact 1: Pollutants have a negative impact on the environment.

Fact 2: Carbon dioxide is a pollutant.

Given the two facts above, answer the question "What affects the environment negatively?" with the following options: 
- sunlight
 - normal weather patterns
 - carbon dioxide
 - cigarettes
 - positivity
 - Smoking
 - harmful substances
 - fossil fuels


 

   carbon dioxide      