What must you do when approaching a solid red traffic light?

When approaching a solid red traffic light, the proper action is to come to a complete stop. This is a critical traffic rule designed to ensure safety at intersections where vehicles and pedestrians may be crossing. Stopping allows drivers to assess the situation, check for any pedestrians in crosswalks, and wait for the light to change to green before proceeding. Traffic lights are fundamental indicators for regulating vehicle flow, and a red light specifically indicates that you must halt your vehicle and not enter the intersection.

Making a U-turn is not permitted at a solid red traffic light unless otherwise indicated, as it can create confusion and lead to dangerous situations. Accelerating to clear the intersection is also unsafe, as it disregards the red light's command to stop and could result in collisions with other vehicles or pedestrians. Similarly, proceeding with caution without stopping is not appropriate, as the law requires a complete stop at a red light before deciding on the next action. Thus, coming to a complete stop is the correct and safe choice when faced with a solid red traffic light.