A Woman Brings Her 11-Month-Old Son to the Office for a Well-Child

A woman brings her 11-month-old son to the office for a well-child visit. When other people approach him, he screams and cries, according to his mother. She is concerned since it has been happening for a few months and appears to be getting worse. She states, "He used to like being held by everyone, but now he only wants to be with me. He won't even let his grandmother hold him." The sufferer is crawling and can only stand with help. He babbles but does not speak well and communicates through hand gestures. Growth curves are tracking well. During the physical examination, the patient clings to his mother and begins to weep, turning his head away from the physician when he tries to connect with him. Which of the following explanations is most likely for this patient's behavior?

A) Adjustment disorder with anxiety
B) Autism spectrum disorder
C) Normal development
D) Reactive attachment disorder
E) Separation anxiety disorder