What is provided to protect aircraft systems powered by the generator and battery buses?

The correct answer, circuit breakers, serves the essential function of protecting aircraft systems powered by the generator and battery buses by interrupting the electrical circuit in case of an overload or fault. This prevents damage to the wiring and connected components by stopping excessive current flow. Circuit breakers are designed to reset after the fault condition is cleared, which allows for quick restoration of power without needing to replace a fuse, making them highly effective in managing electrical faults.

In the context of aircraft systems, maintaining operational integrity and safety is paramount. Circuit breakers are strategically placed throughout the electrical systems to ensure that if one segment experiences an issue, the entire system is not compromised. This localizes the fault and protects other critical components from potential damage.

Other options, while relevant to electrical systems, do not specifically serve the same protective function. Current limiting switches help limit the current but do not provide the same level of interruption as circuit breakers. Surge arrestors protect devices from voltage spikes but do not deal with overload conditions in the same way as circuit breakers. Backup generators support power redundancy but are not directly involved in the protection of circuits during normal operations.