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': 'Cholesteatoma commonly a/w - \nSelect and explain. \nA. Attico-antral, B. Tubotympanic, C. Tympanosclerosis, D. Foreign body in ear', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Tubotympanic type (safe or benign type)\n\nIt is associated with central perforation of tympanic membrane and involves the anterior inferior part of middle ear cleft (eustachian tube and mesotympanum).\nThere is no association with cholesteatoma.\nTubotympanic type is also called safe or benign type as there is no risk of serious complicatiions.\n\nAttico-antral type (unsafe or dangerous type)\n\nIt is associated with an attic or a marginal perforation of the tympanic membrane and involves postero-superior part of middle ear cleft (attic, antrum and mastoid).\nThe attico-antral disease is characterized with cholesteatoma which erodes the bone.\nRisk of intracranial extension of infection, and thus the risk of complication, is very high, therefore it is called dangerous or unsafe ear.', 'role': 'assistant'}]