What is defined as any action on a body that tends to change its size, shape, or state of motion?

The definition in question aligns with the concept of force, which is an interaction that tends to cause a change in the motion, shape, or size of an object. In the context of physics, force can be thought of as a vector quantity that results in an object's acceleration or deformation when applied to it.

When a force is exerted on an object, it can lead to various outcomes: it may cause the object to start moving, stop moving, accelerate, change direction, or alter its shape. This action emphasizes the fundamental relationship between force and motion, highlighting that force is the initiator of change in an object's physical aspects.

Considering the other options, displacement refers to the change in position of an object, not an action causing change itself. Acceleration is the rate of change of velocity of an object, which is a result of the application of force, but it doesn't encompass the concept of changing size or shape. Volume is a measure of the space an object occupies, which is not directly related to the forces acting upon it. Hence, the selection of force as the correct answer signifies its crucial role in the realm of mechanics and motion dynamics.