Fact 1: Condensation causes clouds to form.

Fact 2: Clouds do create rain.

Given the two facts above, answer the question "What causes rain to fall?" with the following options: 
- a hydraulic system
 - Water expanding
 - kinetic energy
 - heating liquids
 - Condensation
 - Evaporation
 - fossil fuels
 - circulatory system


 

     Condensation    