Which of the following is true about the purpose of a ground wire?

The purpose of a ground wire is to provide a safe path for excess electrical current to flow into the ground, thereby ensuring the safety of both the electrical system and the people using it. In the event of a fault, such as a short circuit, the ground wire helps divert the excess current away from sensitive components and individuals, reducing the risk of electric shock or fire. It acts as a protective measure, enabling circuit breakers or fuses to operate effectively and disconnect the power when a fault occurs.

While other functions mentioned, such as enhancing circuit performance or increasing current capacity, are important considerations in electrical design, they are not the primary roles of a ground wire. Instead, the ground wire is chiefly focused on safety by directing harmful excess current safely into the earth.