In a naturally aspirated engine, which technician is right: Technician A claims a pressure difference forces air into the cylinder, while Technician B says piston movement creates this pressure difference?

In a naturally aspirated engine, both statements made by the technicians are correct, which justifies the selection of the answer indicating that both are right.

Technician A is correct in noting that there is a pressure difference that plays a crucial role in drawing air into the engine's cylinders. When the piston moves down during the intake stroke, it creates a low-pressure area (or vacuum) inside the cylinder compared to the atmospheric pressure outside the engine. This difference in pressure allows air from the atmosphere to be forced into the cylinder.

Technician B also correctly points out that piston movement creates this pressure difference. As the piston descends, it increases the volume inside the cylinder, effectively reducing the pressure. This downward movement is essential in facilitating the intake of air, as it initiates the pressure differential that allows external air to flow into the cylinder.

In summary, the operation of a naturally aspirated engine relies on both the movement of the piston to create a pressure differential and the resultant airflow due to that differential. Thus, both technicians' assertions are valid, making the combination of both statements the correct answer.