This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous (E.N.T.), Subject name: ENT
[{'content': 'Most common site involved in Otosclerosis is \nSelect and explain. \nA. Foot plate stapes, B. Malleus head, C. Incus, D. Ear drum', 'role': 'user'}, {'content': "Answer: A \nExplanation: (A) Foot plate stapes # Stapedial Otosclerosis:> Stapedial otosclerosis causing stapes fixation and conductive deafness is the most common variety.> Here lesion starts just in front of the oval window in an area call 'fissula ante fenestram'.> This is the site predilection (anterior focus).> Lesion may be behind the oval window (posterior focus), around the margin of the stapes foot plate (circumferential), in the foot plate but annular ligament being free (biscuit type).> Sometimes, may completely obliterate the oval window niche (obliterative type).", 'role': 'assistant'}]