Fact 1: Electricity is used as an energy source by electrical devices.

Fact 2: Sunlight can be converted to electricity.

Given the two facts above, answer the question "What can be used as an energy source by devices?" with the following options: 
- friction
 - sunlight
 - heat
 - sun's heat
 - Light
 - cells
 - wind
 - oxygen


 

  sunlight       