What is the main purpose of ground fault circuit interrupters (GFCIs)?

The primary purpose of ground fault circuit interrupters (GFCIs) is to interrupt the flow of electricity quickly in the event of a ground fault. A ground fault occurs when there is an unintended path between the source of current and the ground, potentially leading to electric shock or fire hazards.

GFCIs are designed to detect even small differences in electrical current between the live (hot) and neutral wires. If an imbalance is detected, indicating that some current may be leaking to the ground, the GFCI reacts swiftly—typically in less than one-tentieth of a second—to cut off power. This rapid response can significantly reduce the risk of serious injury or death from electrical shock.

While the other choices mention aspects of electrical systems, they do not accurately capture the specific function of GFCIs, which is to enhance safety by providing rapid disconnection of electrical supply when a fault is detected.