Bruce is three years old and is showing some unusual behaviors. He did not babble or point when he was one year of age and did not speak in two-word sentences until well past his second birthday. He does not respond to his name being spoken to him, avoids eye contact with adults, and does not exhibit a normal social smile. He has great difficulty playing with most toys but is so attached to one particular stuffed teddy bear that he screams and wails when his parents try to take it away from him. Which of the following is the most likely cause for Bruce's behavior?
A. Bruce has been socially isolated from his peers but will catch up with them around the age of 11.
B. Bruce has not received enough contact comfort from his mother and father.
C. Bruce has not been exposed to enough spoken language, and he is past the critical period for language development.
D. Bruce has Autism Spectrum Disorder.