What Question Were Gibson and Walk Investigating by Constructing a Miniature

Multiple Choice

What question were Gibson and Walk investigating by constructing a miniature cliff with a drop-off covered by glass in their laboratory? (They placed infants on the edge of this visual cliff and their mothers coaxed them to crawl onto the glass.)

A) How fast can a young child crawl?
B) Can a young child be separated from his mother without concern?
C) How early in life does depth perception develop?
D) Does a child become upset when being tested when the mother does not physically hold the child?