What is the function of a vehicle's brake lights?

Answer: B — To signal to drivers that you are slowing down or stopping

The function of a vehicle's brake lights is to signal to drivers that you are slowing down or stopping. When you apply the brakes, the brake lights illuminate, making it clear to drivers behind you that your vehicle is decelerating or has come to a stop. This visual cue is crucial for maintaining safety on the road, as it allows surrounding drivers to react appropriately—whether that means slowing down, changing lanes, or preparing to stop. Effective communication between vehicles through brake lights helps to prevent collisions and enhances overall traffic flow. In contrast, indicating a turn is achieved by using turn signals, which specifically convey the intent to change direction. The reverse lights serve a different purpose by signaling that a vehicle is backing up. While alerting other drivers to your presence is also important, it is primarily accomplished through headlights or other vehicle positioning rather than specifically by brake lights. Understanding these distinct functions aids in better road safety and driver awareness.