Fact 1: Darkness has a negative impact on photosynthesis.

Fact 2: Plants use photosynthesis to make food.

Given the two facts above, answer the question "What negatively affects plant life?" with the following options: 
- toxins
 - darkness
 - fertilizer
 - water
 - Pesticides
 - Smoking
 - Pollution
 - sunlight


 

  darkness       