What is the first action you should take immediately after stopping the bus?

The correct action to take immediately after stopping the bus is to open the entrance door slightly to activate the stop arms and lights. This is crucial for ensuring the safety of passengers, particularly children who may be boarding or alighting from the bus. Once the door is opened, the bus's stop arms will extend, which actively signals to other road users that they must stop. This helps to create a safe environment for passengers as they enter or exit the bus.

The other options may seem relevant but do not prioritize immediate safety as effectively. Notifying dispatch is important, but it can wait until safety measures are in place. Checking mirrors for traffic is essential but should precede the actual stop; the bus must first be secured for passengers. Waiting for passengers to approach is also important but assumes that the bus is already positioned to safely allow them to do so. Therefore, activating the stop arms and lights is the first and most critical action to ensure everyone's safety.