Fact 1: Powering an electrical device with a battery requires a path for electricity to flow through a closed circuit.

Fact 2: Electrical engineers work on power plants, computers, and other electrical devices.

Given the two facts above, answer the question "A battery-powered computer requires a what for electricity to flow?" with the following options: 
- direct energy
 - closed circuit
 - kinetic energy
 - broken circuit
 - open air
 - hydrogen and oxygen
 - heat energy
 - open circuit


 

  closed circuit       