If clouds lacking water reduces rainfall, then what's one reason it won't rain?

Answer choices:
- fissures of hot, acidic water
 - a hemisphere is tilted away from the sun
 - Warm and cold air meet
 - The clouds don't have enough water
 - The clouds have too much water
 - Too much moisture in the environment
 - decreases the freezing point
 - erosion from rivers

 

    The clouds don't have enough water      