What is the function of a "safety belay" during a rescue?

The function of a "safety belay" during a rescue is to prevent a rescuer from falling in the event that the main line fails. A safety belay serves as a backup system, ensuring the rescuer remains secured even if the primary means of support becomes compromised. This is essential in maintaining safety during operations where there is the potential for slips or equipment failure, thus significantly reducing the risk of injury to the rescuer.

In contrast to other options, a safety belay is not primarily designed to provide an additional route of descent or to assist in lifting the victim, nor is it solely meant to secure the rescue team to an anchor point. Each of those functions relates more to specific equipment or techniques used during the rescue process, whereas the safety belay's core purpose is about fall protection for individuals working above ground.