What type of force occurs when the body is lifted out of the seat toward the ceiling?

When the body is lifted out of the seat toward the ceiling, this phenomenon is best described as experiencing negative Gz forces. Negative Gz refers to the forces acting on the body in a head-up direction, which creates a sensation of weightlessness or being pulled upwards. This typically occurs during rapid climbs or during certain maneuvers in aviation where the vertical acceleration is directed upwards.

In this situation, the body's natural weight, which is normally directed downwards due to gravity, is countered, making it feel as though it is being lifted off the seat. This can lead to various sensations and physiological effects due to the changes in how the body experiences gravitational forces, often felt during flight maneuvers.

In contrast, positive Gz forces would mean that the body is pressed down into the seat, which typically happens during rapid descents or when maneuvers increase vertical acceleration downwards. The other options, negative Gy and positive Gy, pertain to rotational accelerations rather than linear accelerations due to gravitational force acting along the vertical axis. Thus, the context of the question aligns perfectly with the definition of negative Gz forces.