What is the purpose of a ground fault circuit interrupter (GFCI)?

A ground fault circuit interrupter (GFCI) is specifically designed to protect individuals from electric shock. It does this by monitoring the current flowing through a circuit and quickly disconnecting the power if it detects an imbalance, which could indicate that electricity is flowing through an unintended path, such as through a person who is grounded. This rapid disconnection can help prevent severe electrical injuries or fatalities in situations where someone may come into contact with live electrical components.

The other options, while they pertain to different aspects of electrical safety and efficiency, do not capture the primary function of a GFCI. Enhancing circuit performance, extending the life of appliances, and reducing energy consumption do not relate directly to the protection a GFCI offers. Its main goal is safety in environments where electrical hazards are heightened, such as wet areas like bathrooms or kitchens. Thus, the correct answer is to protect against electric shock.