Fact 1: All life relies on a relatively narrow range of pH, or acidity.

Fact 2: Biochemical reactions are catalyzed by enzymes that have very narrow ranges of optimum pH values.

Given the two facts above, answer the question "All what relies on a narrow range where biochemical reactions can be catalyze by enzymes" with the following options: 
- sugar
 - weathering
 - Crops
 - CO 2
 - climate
 - heat
 - life
 - weather


 

       life  