1. The problem asks which number represents that the circuit is "off" or closed. 2. In electrical circuits, the state "off" or closed typically corresponds to a specific binary value. 3. The number zero usually represents the "off" state, meaning no current flows or the circuit is open. 4. The number one usually represents the "on" state, meaning the circuit is closed and current flows. 5. Therefore, the number that represents the circuit being "off" or closed is zero.