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': 'The most Common site of perilymph fistula \nSelect and explain. \nA. Round window, B. Oval window, C. Otic capsule, D. both 1 and 2', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Perilymph fistula: In this condition, perilymph leaks into\xa0the middle ear through the oval or round window.\nIt can follow\xa0as a complication of stapedectomy or ear surgery when\xa0stapes is accidentally dislocated.\nIt can also result from sudden\xa0pressure changes in the middle ear (e.g. barotrauma,\xa0diving, forceful Valsalva) or raised intracranial pressure\xa0(weightlifting or vigorous coughing). A perilymph fistula\xa0causes intermittent vertigo and fluctuating sensorineural\xa0hearing loss, sometimes with tinnitus and sense of fullness in the ear (compare Ménière’s disease).', 'role': 'assistant'}]