What action is NOT permitted regarding the safe operation of a school bus?

Transporting too many passengers is not permitted because it directly compromises the safety of the bus's operation. Each school bus has a specified capacity that considers both the number of seatbelts and the structural design of the vehicle. Exceeding this limit can lead to several dangerous scenarios, including an increased risk of accidents due to lack of space, potential injuries during sudden stops, and challenges in evacuation if an emergency arises.

In contrast, adjusting the seat during transit is unsafe and not allowed because it can distract the driver and lead to loss of control. Driving with open windows can be permissible under certain conditions, though it is subject to regulations regarding passenger safety and potential distractions. Driving without headlights, especially under low visibility conditions, is against safety regulations but does not directly relate to passenger capacity like transporting too many individuals does.