Fact 1: Most ecosystems get energy from sunlight.

Fact 2: On Earth, energy from sunlight heats the atmosphere more at the equator than at the poles.

Given the two facts above, answer the question "Most ecosystems get energy from what in the atmosphere?" with the following options: 
- fires
 - Sun
 - wind
 - summer
 - oxygen
 - Light
 - heat
 - H20


 

       heat  