This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Ear, Subject name: ENT
[{'content': 'Impedance audiometry is for pathology of \nSelect and explain. \nA. External ear, B. Middle ear, C. Mastoid air cell, D. Inner ear', 'role': 'user'}, {'content': 'Answer: B \nExplanation: It is done for the pathology of the middle ear. It is a test for conductive deafness. It is an objective test, widely used in clinical practice and is paicularly useful in children. It consists of: Tympanometry Acoustic reflex measurements. Ref: Dhingra; 6th Edition; pg no 24', 'role': 'assistant'}]