Why is adequate sight distance crucial in highway design?

Answer: B — To ensure drivers can see and react to obstacles safely

Adequate sight distance is essential in highway design primarily because it allows drivers sufficient time to see obstacles ahead and react safely. This distance enables drivers to perceive any potential hazards, such as pedestrians, animals, or stopped vehicles, and make necessary adjustments, whether it's slowing down, changing lanes, or stopping completely. Ensuring that drivers can see far enough ahead is a vital safety component that helps prevent accidents and enhance overall road safety. While there may be other considerations like aesthetic views, land acquisition costs, or emergency vehicle access, they do not directly contribute to the fundamental need for safety and driver response in a comprehensive and effective manner. Sight distance directly impacts how well drivers can navigate the road and avoid unforeseen circumstances, which is why it is prioritized in highway design.