You are answering a USMLE-style medical question. Question: A 12-year-old girl is brought to your psychiatry office by her parents, who are concerned that she has not made any friends since starting middle school last year. The girl tells you that she gets nervous around other children, as she cannot tell what they are feeling, when they are joking, or what she has in common with them. Her teachers describe her as “easily distracted” and “easily upset by change.” When asked about her hobbies and interests, she states that “marine biology” is her only interest and gives you a 15-minute unsolicited explanation of how to identify different penguin species. Mental status exam is notable for intense eye contact, flat affect, and concrete thought process. Which of the following is true regarding this child’s disorder? Options: A) Boys are more commonly affected than girls B) Impaired attention is a key feature of the disorder C) Intellectual disability is a key feature of the disorder D) Typical age of onset is 3-5 years of age Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.