A retarding force on a body does not A. Change the motion of the body B. Retard the motion of the body C. Introduce the motion of the body D. None of these

The correct answer is: A. Change the motion of the body.

A retarding force is a force that opposes the motion of an object. It can cause the object to slow down, stop, or change direction.

Option B is incorrect because a retarding force does retard the motion of the body.

Option C is incorrect because a retarding force does not introduce the motion of the body. The motion of the body must already be present in order for a retarding force to act upon it.

Option D is incorrect because only option A is correct.