You need to be able to see at least _________ feet before making a U-turn at the crest of a hill or an intersection.

To safely execute a U-turn at the crest of a hill or an intersection, it is crucial to have adequate visibility of the oncoming traffic. The requirement to see at least 500 feet ensures that a driver has sufficient time to react and assess the situation effectively. This distance allows for a clear view of both the intersection and any potential hazards, such as other vehicles or pedestrians. By being able to see far enough ahead, the driver can make a well-informed decision and ensure the safety of everyone on the road.

Other distance options, while they may seem substantial, do not provide the same level of assurance in terms of visibility and reaction time necessary for such a maneuver, especially in areas where visibility can be obscured by terrain or traffic. Thus, the correct answer highlights the importance of safety and awareness when considering a U-turn in potentially hazardous locations.