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': 'Otosclerosis shows which type of tympanogram? \nSelect and explain. \nA. Type A, B. Type B, C. Type C, D. Type D', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Type A tympanograms have normal peak height and pressure. Two variations of the Type A tympanogram also are normal in pressure, but may be shallow (AS), reflecting otosclerosis or middle ear effusion, or peaked very high (AD), reflecting ossicular discontinuity or a monomeric eardrum', 'role': 'assistant'}]