Which maneuver should be used if a lifeguard encounters a victim that is face down in the water?

The simple lift and flip technique is the most effective and appropriate maneuver for a lifeguard to use when encountering a victim who is face down in the water. This technique allows the rescuer to quickly and safely turn the victim onto their back, which is crucial for checking their airway and initiating rescue breathing if necessary.

Upon flipping the victim, the lifeguard can more easily assess their condition. Keeping the victim face-up is essential for effective monitoring and providing aid, as it helps prevent drowning and allows for better access for potential resuscitation efforts.

The other options, while they may seem plausible under different circumstances, do not prioritize the immediate need for turning the victim onto their back to ensure their safety. For example, a complex rescue roll may introduce unnecessary risks and complications, especially in an open water scenario. A dive under to retrieve the victim could potentially endanger the lifeguard as well as the victim, and a backstroke carry might not be efficient or safe without first ensuring that the victim is in a suitable position for safe transport.