You are presented with the question "What causes low amounts of precipitation?" and the following answer choices: 
- Plant growth is reduced
 - a hemisphere is tilted away from the sun
 - more condensation
 - extra moisture in the air
 - excess water supply
 - fissures of hot, acidic water
 - lack of moisture in the air
 - a tree falling

Now knowing that lack of moisture in the air causes low amounts of rainfall and rainfall is just one form of precipitation, choose the best answer.


 

       lack of moisture in the air  