Describe the purpose of a control valve in a fire sprinkler system.

The purpose of a control valve in a fire sprinkler system is to control the flow of water within the system. Control valves are essential in managing the water supply, allowing for the isolation of specific sections of the sprinkler system for maintenance or repairs without affecting the entire system's operation. They can also regulate the water flow to ensure that the necessary pressure and volume are available at the sprinkler heads when needed during an emergency. This function is crucial, as sufficient water flow is necessary to effectively combat a fire.

In the context of a fire sprinkler system, the control valve ensures operational efficiency and safety, making it a vital component for both functionality and reliability during fire suppression efforts. The other choices revolve around aspects that do not directly relate to the primary role of control valves in managing water flow, which emphasizes the importance of understanding the specific functions of such components within fire protection systems.