Final answer:
Getting passengers on and off the aircraft is the responsibility of the cabin crew, specifically the flight attendants, while pilots focus on aircraft operation and ground crew handle tasks outside the plane.
Step-by-step explanation:
The responsibility of getting passengers on and off the aircraft primarily lies with the cabin crew, which includes flight attendants. They are in charge of ensuring passengers board the plane safely, find their seats, and disembark in an orderly fashion after the plane has landed and arrived at the gate. The pilots, meanwhile, are primarily responsible for operating the aircraft, including running through pre-flight checklists and ensuring the safety of the flight. The ground crew has responsibilities outside the plane, such as handling baggage, marshaling the aircraft, and various tasks related to airport operations.