When must a driver activate the school's warning lights?

The correct response is that a driver must activate the school's warning lights when approaching a school zone or when students are boarding or exiting. This action is critical for ensuring the safety of children who are getting on or off the bus, as well as other pedestrians around school zones. Activating the warning lights alerts other drivers to slow down and be cautious, signaling that children may be present and crossing the street.

This practice is guided by traffic laws that prioritize the protection of vulnerable road users, particularly in areas where students are likely to interact with vehicular traffic. Adhering to this requirement helps reduce the risk of accidents and creates a safer environment around schools.

Other options, such as using the lights only during heavy traffic or when the bus is in motion continuously, do not adequately address the specific scenario where students are at risk. Additionally, turning on the lights at the bus garage is not relevant as it does not involve engaging with traffic or interacting with students. The emphasis is placed on the times when student safety is most at stake.