Question

Which describes the use of a renewable energy source?
burning natural gas to power city buses
using solar cells to heat water for use in homes
burning coal to operate the machinery in a factory

Answer 1

Out of the choices, solar energy is the renewable energy resource. So the answer is using solar cells to heat water.  

Answer 2

solar energy is a renewable energy source so C. the using of solar cells to heat water for use in homes would be correct