Final answer:
Most public vehicles, including buses, must stop at railway crossings. This safety measure is to prevent potential collisions with trains and is a common legal requirement.
Step-by-step explanation:
Most buses and other public vehicles are required to stop at railway crossings. This regulation helps ensure the safety of passengers by preventing collisions with trains. Buses must stop moving and become stationary until it is clear to proceed, regardless of whether a train is visible or not. Different local laws and regulations may dictate specific actions, such as opening the door to listen for an oncoming train, but stopping is a common legal requirement for larger vehicles like school buses and hazardous material carriers at all railroad crossings.