<prompt> Cholesteatoma occurs in:CSOM with central perforationMasked mastoiditisCoalescent mastoiditisAcute necrotising Otitis media  <response>: d Acute necrotising Otitis mediaRef. Cummings, 6th ed., 2146The MC route of secondary cholesteatoma is migration of keratinising stratified squamous epithelium through marginal perforation of TM.This marginal perforation follows ANOM.Rest of the choices are not associated with cholesteatoma. 