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

Fact 2: An electrical current is a flow of electrons.

Given the two facts above, answer the question "Powering a device with a battery requires a path for electrons to flow through  " with the following options: 
- electromagnetic energy
 - direct energy
 - rays or beams
 - hydrogen and oxygen
 - heat energy
 - a closed circuit
 - kinetic energy
 - an object


 

      a closed circuit   