A GFCI monitors the imbalance of current between which conductors?

A Ground Fault Circuit Interrupter (GFCI) is designed to monitor the balance of electrical current flowing in and out through the conductors. It specifically detects any differences in current between the hot and the grounded (or neutral) conductors.

The purpose of a GFCI is to provide a safety mechanism that can identify potentially harmful ground faults, which occur when electricity flows through an unintended path, such as water or a person. If the GFCI detects that there is a disparity in current — meaning more current is returning through the hot wire than is flowing back through the neutral wire — it will trip (i.e., break the circuit) to reduce the risk of electric shock.

In this context, the correct answer emphasizes the relationship between the hot conductor and the ground. Although the other options present different pairings, the fundamental working of a GFCI focuses on the imbalance between the current in the hot and neutral conductors, which is critical for its function in protecting against electrical hazards. Understanding this ensures that GFCIs are appropriately installed and utilized in locations where there is an increased risk of electric shock, such as kitchens and bathrooms.