What safety measure is provided by circuit breakers?

Circuit breakers are crucial safety devices that regulate current within an electrical circuit. Their primary function is to detect overloads or short circuits and interrupt the flow of electricity to prevent damage to the electrical system and reduce the risk of fire. By monitoring the current, circuit breakers protect wiring, appliances, and equipment from excessive heat that could lead to failure or hazardous conditions.

In the context of the other options, regulating pressure in pipes and controlling water flow are functions associated with hydraulic systems, not electrical circuits. Monitoring water temperature pertains to thermal systems, commonly dealt with in heating and cooling applications, rather than focusing on the electrical regulation that circuit breakers provide. Thus, the role of circuit breakers is clearly centered on current regulation, making it the appropriate answer.