This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Gynaecology & Obstetrics
[{'content': 'A woman delivers a 91b infant with a midline episiotomy and suffers a third degree tear. Inspection shows which of the following structures is intact : \nSelect and explain. \nA. Anal sphincter, B. Perineal body, C. Parineal muscles, D. Rectal mucosa', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Rectal mucosa', 'role': 'assistant'}]