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': 'Iatrogenic traumatic facial nerve palsy is most commonly caused during - \nSelect and explain. \nA. Myringoplasty, B. Stapedectomy, C. Mastoidectomy, D. Ossiculoplasty', 'role': 'user'}, {'content': 'Answer: C \nExplanation: “All ear operations run the risk of facial nerve damage, particularly if the nerve is exposed. In particular a mastoidectomy has a high risk because a sharp cutting rotating burr is used in close proximity to the nerve.”\nOther Operations where Facial Nerve may be Damaged\n– Stapedectomy\n– Removal of acoustic neuroma', 'role': 'assistant'}]