It Is Difficult to Study the Forgetting of Perceptual-Motor Skills

Multiple Choice

It is difficult to study the forgetting of perceptual-motor skills because:

A) once a skill is learned, it is never forgotten.
B) if a person cannot perform a skill, it usually means she has forgotten it.
C) without practice, the ability to perform a skill tends to deteriorate.
D) it is difficult to distinguish forgetting of the skill from impairment in motor control.