What is the function of a GFCI outlet?

The function of a GFCI (Ground Fault Circuit Interrupter) outlet is to prevent electrical shock. GFCI outlets are specifically designed to protect people from the dangers of electric shock by monitoring the flow of electricity in a circuit. If they detect an imbalance between the incoming and outgoing current - which can happen if electricity is leaking to the ground, such as through a person accidentally making contact with a live wire - the GFCI quickly shuts off the power to that circuit. This rapid response can help prevent serious injuries or fatalities resulting from electrical shock.

Other choices do not align with the primary function of a GFCI outlet. Increasing electrical voltage does not relate to safety and can indeed make shock hazards worse. Serving as a power switch is not a feature of GFCI outlets, as their role is focused on protection rather than control of the power flow. Measuring electrical current is a function associated with devices like ammeters or multimeters, not GFCIs, which are purely protective devices.