Fact 1: Most ecosystems get energy from sunlight.

Fact 2: Lakes and rivers are extremely complex ecosystems.

Given the two facts above, answer the question "Where do lakes get energy from?" with the following options: 
- a delta
 - water
 - petroleum
 - sun's heat
 - gasoline
 - Evaporation
 - sunlight
 - heat


 

       sunlight  