Fact 1: Air pollution can cause the pH of soil to decrease.

Fact 2: Highly acid soil is detrimental to crop growth and biological activity in soil.

Given the two facts above, answer the question "Crop growth can be negatively impacted by" with the following options: 
- fossil fuels
 - light pollution
 - Pollution
 - drought
 - rainbow falls
 - Greenhouse gasses
 - lunar eclipse
 - air pollution


 

        air pollution 