What is indicated by the entry lights, stairway lights, and warning light when the door is operated?

When the door is operated, the entry lights, stairway lights, and warning light illuminate to provide visibility and safety for passengers as they enter or exit the bus. This illumination serves multiple purposes: it helps passengers see the steps and surroundings, enhances overall safety, and alerts other drivers and pedestrians that the bus doors are open.

The design to have these lights illuminate as the door operates is intentional, ensuring that anyone using the entrance has the necessary illumination to do so safely. The functionality is specifically meant to enhance safety during the boarding and alighting process, making it easier for passengers to navigate the stairs and alerting oncoming traffic.

In contrast, the other options describe scenarios that do not align with the operational standards of transit buses. For instance, the lights do not turn off immediately nor do they only work when the bus is running. Additionally, the illumination of these lights does not indicate a malfunction; instead, it indicates the standard operational condition when the door is engaged.