Jeff Coggins is a 12 year-old youngster who has always been seen by his teachers as
"hard to manage." Recently, he started to have new episodes of temper outbursts that are
clearly out of proportion to the situation. Which of the following diagnoses is not a
possibility?

a) Bipolar disorder
b) Disruptive mood dysregulation disorder
c) Attention-deficit/hyperactivity disorder
d) Conduct disorder