If You Hold Your Hand in Front of You at Arm's

Multiple Choice

If you hold your hand in front of you at arm's length,you recognize it as your hand.If you slowly move your hand in toward your face,the image of your hand covers a larger portion of your retina,however,you do not tend to think that your hand has suddenly begun to grow.Which of the following explains this?

A) colour constancy
B) Ponzo illusion
C) Muller-Lyer illusion
D) size constancy