What is the purpose of activating the amber lights on a school bus?

Activating the amber lights on a school bus serves the critical purpose of warning drivers that the bus is preparing to make a stop to load or unload students. When these lights are illuminated, it signals to drivers that they should reduce their speed and be alert to the possibility of children entering or exiting the bus. This precaution is essential for safety, as it helps prevent accidents by preparing drivers for the actions that will follow, ensuring that everyone remains safe during these potentially hazardous moments.

In contrast to the other options, the amber lights are not used to indicate the end of a route or to signal a bus malfunction. They do not indicate the moment when students may board; rather, they serve as an early warning system before the red stop lights are activated when the bus comes to a complete halt.