Blind human children:

A) do not smile.
B) show abnormal musculature when they smile.
C) show the same facial expressions as sighted children.
D) must be trained, using the tactile sense, to show facial expressions.

Facial Expressions

The movements of the facial muscles that convey emotions, intentions, and social information to others.

Tactile Sense

The sense of touch, which enables organisms to perceive and interpret information through physical interaction with their environment.