What is the primary purpose of a stop sign?

Answer: B — To require drivers to come to a complete stop

The primary purpose of a stop sign is to require drivers to come to a complete stop. This traffic control device is specifically designed to ensure that vehicles come to a full halt before proceeding. It is typically placed at intersections where visibility may be limited or where traffic may have right-of-way considerations. By necessitating a complete stop, the stop sign helps to enhance safety by allowing drivers to assess oncoming traffic and pedestrians, thus reducing the likelihood of accidents. While yielding is an important concept in traffic management, it does not capture the intent of a stop sign, which mandates a full stop. Slowing down is also essential in driving but is not synonymous with the action required by a stop sign. Similarly, indicating the end of a road does not apply, as stop signs are specifically about controlling traffic at intersections rather than indicating road terminations.