Final answer:
At an uncontrolled intersection, the driver on the left must yield to the driver on the right. Traffic signals play a crucial role in managing vehicle flow and ensuring pedestrian safety at busy intersections.
Step-by-step explanation:
If two vehicles approach an uncontrolled intersection at about the same time, the correct answer to who must yield is: c. The driver on the left yields to the driver on the right. This rule is part of standard traffic laws which dictate right-of-way protocol to prevent accidents and ensure a smooth flow of traffic. The driver on the right generally has the right-of-way at intersections when drivers arrive at the same time.
In terms of safety, a traffic signal at busy intersections can help manage the flow of vehicles and safeguard pedestrians. It requires vehicles to slow down and stop when necessary, providing organized opportunities for all traffic, including pedestrians, to move through the intersection safely.