You are presented with the question "In order to operate at night, solar-powered LED lights require what?" and the following answer choices: 
- sun's heat
 - electrically
 - adding heat
 - focusing a lens
 - hydrogen and oxygen
 - kinetic energy
 - electrical energy
 - direct energy

Now knowing that alight bulb requires electrical energy to produce light and solar-powered lights that use LED bulbs provide the most efficient and most hours of light at night, choose the best answer.


 

       electrical energy  