Scientists Created a Visual Cliff by Placing a Thick Sheet

Multiple Choice

Scientists created a visual cliff by placing a thick sheet of clear glass over a drop-off. They found that by the time children are old enough to crawl, they will not venture over the "edge" of the "cliff." What skill have the children developed that makes them wary?

A) convergence
B) perceptual constancy
C) the law of proximity
D) depth perception
E) problem solving