This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Complications of Chronic Otitis Media, Subject name: ENT
All of the following are the uses of given instrument except : 
Select and explain. 
A. Harvesting Temporalis fascia, B. Self retaining and haemostatic, C. In mastoidectomy to retract soft tissues after incision, D. Helps in removal of bone
D: Helps in removal of bone
Answer: D: Helps in removal of bone 
Explanation: Mollison's mastoid retractor Self retaining mastoid retractor with four prongs on either blade USES- Harvesting Temporalis fascia Used in mastoidectomy to retract soft tissues after incision and elevation of flaps It is self retaining and haemostatic Mastoid Gouge -Help in removal of bone Perkin's mastoid retractor has 1x3 prongs