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: ENT
[{'content': '1st Branchial cleft anomaly \nSelect and explain. \nA. Amotia, B. Pre-Auricular sinus, C. Call-Aural fistulo, D. Absence of Tragus', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]