Justin, a 9-Year-Old Boy, Has Been Given Detention Several Times

Justin, a 9-year-old boy, has been given detention several times within the last 8 months for unruly and disruptive behavior during class. His teachers have reported that he often talks back and is rude toward them. He disobeys his parents and frequently fights with his siblings. Justin does not have any friends at school, as other children are put off by his behavior. He is most likely to be diagnosed with

A) oppositional defiant disorder.
B) school phobia.
C) generalized anxiety disorder.
D) pervasive developmental disorder.