Rebecca's New Boyfriend Andy Takes Her to a 3-D Movie

Rebecca's new boyfriend Andy takes her to a 3-D movie. In an effort to impress Rebecca, Andy explains to her that the movie appears to be three-dimensional by providing each eye with slightly different images, thus creating the illusion of depth. Andy can't remember what this phenomenon is called, but Rebecca, tired of Andy's showing off, tells him it is called

A) ocular accommodation.
B) retinal disparity.
C) a stroboscopic illusion.
D) shape constancy.