Fact 1: Lack of moisture in the air causes low amounts of rainfall.

Fact 2: Most precipitation occurs as rainfall.

Given the two facts above, answer the question "what does lack of moisture in the air cause low amounts of?" with the following options: 
- Calcium carbonate
 - harmful substances
 - volume
 - precipitation
 - smog
 - drought
 - flooding
 - weathering


 

    precipitation     