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
Central pa of cholesteatoma contains ? 
Select and explain. 
A. Keratin debris, B. Keratinized squamous epithelium, C. Coulmnar epithelium, D. Fibroblasts
A: Keratin debris
Answer: A: Keratin debris 
Explanation: Ans. is 'a' i.e., Keratin debris Cholesteatoma Destructive or expanding growth in the middle ear or mastoid process The term cholesteatoma is a misnomer, because it neither contains cholesterol crystals nor is it a tumor to merit the suffix `oma'. Cholesteatoma has the propey to destroy bone. It may cause destruction of ear ossicles, erosion of bony labyrinth, canal of facial nerve, sinus plate or tegmen tympani and thus cause several complications. Bone destruction by cholesteatoma has been attributed to various proteolytic enzymes liberated by osteoclasts and mononuclear inflammatory cells, seen in association with cholesteatoma. Cholesteatoma consists of two pas : ? i) Matrix : - Made up of keratinizing squamous epithelium. ii) Keratin debris (central white mass) : - Produced by the matrix. Therefore, cholesteatoma also referred to as epidermosisor keratoma.