Mr. and Mrs. Williams and their two-year-old son, Michael, are seeing Dr. Browne at the Whitestone Pediatric Clinic. The parents are concerned with behavior patterns Michael has been exhibiting. When brought to the examination room, the nervous parents explain to the pediatrician that Michael very rarely shows facial expression. As an infant, Michael would exhibit an eye-to-eye gaze, and now he would rather play alone for hours than engage with other children or adults. Michael becomes enraged if interrupted.
Based on Michael's symptoms, you would suspect _______ to be the physician's diagnosis.
A. cystic fibrosis
B. Down syndrome
C. failure to thrive
D. autism