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: Orthopaedics
[{'content': 'A 5 year old child with high grade fever and reduced movement at left knee, diagnosed with osteomyelitis, gold standard investigation is \nSelect and explain. \nA. MRI, B. Bone scan, C. Biopsy, D. X-ray', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]