Which of the following devices is designed for overload and short circuit protection?

The correct answer is a miniature circuit breaker because it is specifically designed to provide protection against both overloads and short circuits in electrical systems. An overload occurs when the current flowing through a circuit exceeds its rated capacity, while a short circuit happens when there is a fault causing a direct connection between the live and neutral conductors, often resulting in a sudden surge of current.

Miniature circuit breakers automatically disconnect the electrical circuit when they detect these dangerous conditions, thereby preventing potential damage to wiring and devices, as well as reducing the risk of fire. They are an essential safety component in residential and commercial electrical installations.

In contrast, a surge protector is primarily intended to prevent voltage spikes from damaging electronic devices, a ground fault circuit interrupter monitors the current flowing through conductors to quickly cut power in the event of ground faults, and a voltage regulator is used to maintain a constant voltage level in a system rather than providing direct protection against overloads and short circuits.