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

Fact 2: Weather changes from season to season.

Given the two facts above, answer the question "What causes weather changes?" with the following options: 
- the moon
 - the earth orbiting the sun
 - degrees Celsius
 - the environment
 - agriculture
 - Greenhouse gases
 - global warming
 - rivers


 

  the earth orbiting the sun       