A 10-year-old child is referred by the pediatrician for a psychiatric evaluation due to concerns about academic difficulties and depression.The child's teachers report that the child appears inattentive, distractible and often replies to questions with long, wandering statements that are disorganized and off-topic. The child also talks about seeing dragons coming to get him, and once hid under the desk. During recess the child sits alone and does not make an effort to interact with peers. The parents report that they can hardly get the child to smile, and that they have to provide guidance for once-simple tasks. On mental status examination, the child appears distractible and generally inattentive and uninterested. He appears to have difficulty understanding questions, and his answers are rambling, disjointed statements. Which of the following is the most likely diagnosis?
A. Major depressive disorder
B. Early-onset schizophrenia
C. Separation anxiety disorder
D. Generalized anxiety disorder
E. Attention-deficit hyperactivity disorder (ADHD), inattentive type