Answer - C - There is no event that would suggest Adjustment Disorder is a cause here. His conduct is not really out of line, considering everything else that’s going on for him. And if his conduct is not really out of line, the Oppositional Defiant Disorder doesn’t really fit, either. Disintegrative Disorder is where children lose certain abilities that were easily learned before age 10, with intermittent recovery. James should be referred to a Psychologist and the IEP may need to be revised to adjust for the regression that is occurring.