As a Door Opens Toward You, You Perceive It as a Rectangular

Multiple Choice

As a door opens toward you, you perceive it as a rectangular door. As you go through the door, the actual image changes on the retina (from rectangular to trapezoid) . However, you still recognize it as a rectangular door. This is an example of

A) perceptual closure.
B) shape constancy.
C) ambiguous stimuli.
D) retinal disparity.