Fact 1: Sunlight and rain can cause a rainbow.

Fact 2: Cold fronts bring in the rain.

Given the two facts above, answer the question "What can cause a rainbow?" with the following options: 
- sunlight
 - cold fronts
 - heating liquids
 - earthquakes
 - the moon
 - solar eclipse
 - a prism
 - evaporation


 

  cold fronts       