What is the function of the red flashing lights on a school bus?

The function of the red flashing lights on a school bus is to warn other drivers to stop. When these lights are activated, it indicates that the bus is either picking up or dropping off children, and all motorists must halt their vehicles to ensure the safety of the students. This is a crucial safety measure designed to protect children who may be crossing the road or entering the bus. Compliance with this signal is not just a recommendation; it is mandated by law in most states to ensure that children can safely board or exit the bus without the risk of injury from passing vehicles.

The other options do not accurately represent the primary function of the red flashing lights. While signaling turns or indicating that the bus is about to leave a stop may require different lights or signals, they do not specifically call for stopping as a critical safety measure at pick-up and drop-off points. Similarly, the lights do not merely show that the bus is in operation; they serve a distinct role in communicating to other drivers to protect vulnerable passengers, particularly children, during those critical moments.