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: Surgery
[{'content': 'Ring sequestrum is seen in? \nSelect and explain. \nA. Typhoid osteomyelitis, B. Chronic osteomyelitis, C. Amputation stump, D. Tuberculosis osteomyelitis', 'role': 'user'}, {'content': "Answer: C \nExplanation: Excessive periosteal stripping is contraindicated as it may result in formation of ring sequestrum in amputation stump. Type of sequestrum Found In Ring sequestrum Amputation stump Around pin tracts ( external fixator) Tubular sequestrum Hematogenous osteomyelitis Segmental fractures ( middle segment) Rice grain sequestrum Tuberculosis Ref: Campbell's operative Ohopaedics 10/e, page 544.", 'role': 'assistant'}]