When Visiting Your Sister, You Notice That Her Infant Enjoys

When visiting your sister, you notice that her infant enjoys watching a mobile that hangs over his head.Of the various objects hanging on the mobile, which ones are likely to get more of his attention?

A) red ones, because infants are particularly responsive to this color
B) gray ones, because these are least frightening to a child
C) ones with bold black-and-white patterns, because patterns with high contrast are most interesting to an infant
D) objects with simple shapes, because these are easier for the infant to recognize