What should a driver do immediately before picking up students?

The correct action a driver should take immediately before picking up students is to ensure that traffic has stopped prior to opening the door. This step is critical for ensuring the safety of the children. By confirming that vehicles have halted, the driver minimizes the risk of an accident, as children are often excited and may not be fully aware of their surroundings.

Activating hazard lights, while an important safety measure to signal to other drivers, does not guarantee that traffic will stop. Properly adjusted mirrors are essential for overall safe operation but are not specifically tied to the immediate act of picking up students. Checking the fuel level is important for ensuring that the bus can operate without interruption, but it is not a direct concern at the moment of safely picking up students. Thus, confirming that traffic has stopped is the most critical and responsible action to take before opening the door to let students on board.