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': 'Coical mastoidectomy in indicated in: \nSelect and explain. \nA. Cholesteatoma without complication, B. Coalescent mastoiditis, C. CSOM with brain abscess, D. perforation in Pars flaccida', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Schwaz operation is another name for coical/sample mastoidectomy', 'role': 'assistant'}]