Which of the following is a prohibited practice while operating a bus?

The manual lists practices a bus driver must avoid. Among them: fueling the bus with passengers aboard, especially in a closed building, unless absolutely necessary; engaging in conversation or activity that distracts from safe driving; and refueling or doing other tasks that put passengers at risk. Drivers must also not allow riders to stand forward of the standee line, leave the bus when passengers are aboard except as permitted, or carry prohibited hazardous materials. These rules exist because the driver's full attention and the passenger area's safety cannot be compromised while people are on board.