A circuit that contains a complete path for electrons to flow through is a closed circuit.

• A. Open circuit
• B. Closed circuit
• C. Short circuit
• D. Grounded circuit

Answer: (B)

Current can flow only when there is a complete loop for electrons to travel. When a circuit has a continuous path from the power source, through conductors and any devices, and back to the source, electrons move in a loop and energy is delivered—this is a closed circuit. If the path is broken anywhere, such as by an open switch or a loose connection, there is no complete loop and current stops—that’s an open circuit. A short circuit is a type of closed path that bypasses the intended load and often carries too much current due to very low resistance, which is different from the normal functioning closed circuit. Grounding relates to safety by connecting the circuit to earth, not to whether the current path in the normal circuit is closed. So the statement matches the idea that a closed circuit has a complete path for electrons to flow.