Fact 1: Earth orbiting the Sun causes seasons to change.

Fact 2: More than any other season, summer is a time of quick-changing weather patterns.

Given the two facts above, answer the question "Earth doing what causes quick-changing weather patterns?" with the following options: 
- orbiting the sun
 - Greenhouse gases
 - cycling the moon
 - global warming
 - soaking up rays
 - energy of moving objects
 - drifting in space
 - Movement


 

 orbiting the sun        