One benefit of using a spotter while backing an ambulance is:

Using a spotter while backing an ambulance primarily enhances visibility. The spotter serves as an additional set of eyes, allowing for a clear perspective of hazards that the driver may not see through mirrors or direct line of sight. Emergency situations often occur in environments with limited visibility, such as crowded areas or during low-light conditions. The spotter can communicate real-time information about obstacles or changes in the surroundings, which significantly reduces the risk of accidents.

While the other options present useful concepts, they do not accurately capture the main advantage of having a spotter. For instance, the use of mirrors is still vital, and a spotter does not replace that function but rather complements it. Additionally, the focus is on safe and careful maneuvering rather than speed, ensuring that all actions taken when backing up prioritize safety. Regular communication is essential in all aspects of emergency response, but the primary benefit in this context is indeed the enhanced visibility that a spotter provides.