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
Treatment of choice for perforation in pars flaccida of the tympanic membrane with cholesteatoma is - 
Select and explain. 
A. Myringoplasty, B. MRM-Modified Radical Mastoidectomy, C. Antibiotics, D. Radical mastoidectomy
B: MRM-Modified Radical Mastoidectomy
Answer: B: MRM-Modified Radical Mastoidectomy 
Explanation: CSOM is of Two Types