Which of the following describes a shut-off valve?

A shut-off valve is specifically designed to stop the flow of water within a piping system. This function allows users to quickly and effectively halt water flow for various reasons, such as maintenance, repairs, or emergencies. Identifying this valve as one that can shut off the water flow underscores its primary purpose in managing water supply and system control.

The other options, while related to valves, do not specifically describe the unique function of a shut-off valve. For instance, valves that control water pressure, distribute water, or drain water have different roles within plumbing and water management systems, which do not focus solely on the ability to completely stop water flow. Thus, recognizing the core function of a shut-off valve as being solely for shutting off water flow is essential for proper understanding and application in related contexts.