What Evidence Do We Have for Believing That People Have

What evidence do we have for believing that people have built-in, unlearned tendencies for certain facial expressions?

A) Humans use facial expressions to express emotions and other primates do not.
B) Children who are born deaf and blind develop normal facial expressions.
C) People use various facial expressions throughout the day, even when they are feeling no emotions.
D) People in all parts of the world laugh equally frequently and they laugh at the same things.