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': 'Fluctuating recurring variable sensorineural deafness is seen in - \nSelect and explain. \nA. Serous otitis media, B. Heamotympanum, C. Perilabyrinthine fistula, D. Labrinthine concussion', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]