Fact 1: Darkness has a negative impact on photosynthesis.

Fact 2: Light is necessary for photosynthesis, a process that produces oxygen.

Given the two facts above, answer the question "Darkness has a negative impact on which process of a plant?" with the following options: 
- slow and inefficient
 - chemical changes
 - circulatory systems
 - most organisms
 - fossil fuels
 - Abnormal cell growth
 - deoxyribonucleic acid
 - Oxygen production


 

        Oxygen production 