An operator passing another vehicle must return to an authorized lane before coming within __________ feet of an approaching vehicle.

The correct answer is 200 feet. This distance requirement is in place to ensure safety when an operator is passing another vehicle. It allows enough space for the vehicle being overtaken and the approaching vehicle to maintain a safe distance from each other, minimizing the risk of collisions. By requiring drivers to return to their lane before coming within 200 feet of oncoming traffic, the rule helps establish a buffer zone that enhances visibility and reaction time for all drivers involved. This regulation emphasizes the importance of safe passing practices on the road, ensuring that drivers are aware of their surroundings and the distance necessary for maneuvers that could affect the flow of traffic.