Where should a guide stand when backing a large vehicle?

The correct response highlights the importance of visibility for safe maneuvering. When backing a large vehicle, the guide should stand at the rear of the vehicle within the driver’s visibility. This position allows the guide to communicate with the driver effectively while also remaining in sight. The guide can visually assess the surroundings, alerting the driver to any obstacles or hazards that are not visible from the driver’s seat.

Standing at the rear ensures that the driver can see the guide clearly, creating a safer environment for backing maneuvers. The guide's role is crucial in preventing accidents, as they are responsible for monitoring the area that is typically blind to the driver, especially with larger vehicles that have significant blind spots.

Other positions, such as at the front, on the side, or on the roof, would be less effective for different reasons – these could obstruct visibility, hinder communication, or create safety concerns.