This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Orthopaedics
[{'content': 'Most common tumor of vertebral spine in adults \nSelect and explain. \nA. Secondary deposits, B. Multiple myeloma, C. Lymphoma, D. Hemangioma', 'role': 'user'}, {'content': 'Answer: A \nExplanation: (A) Secondary deposits> Most common secondary deposits from visceral primary malignancy occurs in the site of vertebral spine.> Most common primary bone marrow malignancy is multiple myeloma> Most common primary malignant bone tumor is osteosarcoma.', 'role': 'assistant'}]