When is it most appropriate to flash your brake light?

Answer: C — When you will be slowing suddenly

Flashing your brake light is most appropriate when you will be slowing suddenly. This practice serves as a warning to drivers behind you that you are about to reduce your speed quickly, which can help prevent potential collisions. By signaling your intention to slow down in a sudden manner, you give other road users adequate notice to adjust their speed and maintain a safe following distance. In situations like heavy traffic or when another rider is near, the need for a sudden change in speed may not be evident to other road users, and flashing the brake light may not convey the urgency needed. While coming to a complete stop does warrant use of the brake light, it is typically sufficient to simply activate the brake light without the need for flashing, as a consistent brake light is clear enough for drivers to recognize that you are stopping.