What Final Condition Must Be Met in Order to Smile

What final condition must be met in order to smile, laugh, and appreciate a joke? The listener must

A) detect the unresolvable incongruity between the joke's expected ending and punch line.
B) be able to control the level of arousal that the punch line produces.
C) be in a social setting with other people present when the joke is told.
D) assimilate the punch line into an alternative schema that resides in the joke stem.