What Is Implied by the Phenomenon of Perceptual Constancy

What is implied by the phenomenon of perceptual constancy

A)  Movement of an object can disrupt our ability to perceive it. 
B)  Two objects may be perceived as being the same even though they produce different retinal images. 
C)  We have an easier time remembering items that have remained constant, compared to objects that have changed. 
D)  Our ability to perceive changes in an object is inhibited if we have been exposed to that object for an extended period of time.