A micro expression refers to?

A) a very brief, involuntary expression of emotion.
B) any false expression that masks the person's true feelings
C) a self report technique for measuring briefly experienced feeling states.
D) an emotion that is not intensely experienced.

Micro Expression

Brief, involuntary facial expressions that reveal true emotions, often occurring when a person is trying to conceal their feelings.

Involuntary Expression

Unconscious facial or bodily movements that convey emotions or reactions, not controlled voluntarily.