This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Skeletal Infections, Subject name: Orthopaedics
[{'content': 'TB spine most commonly affects? \nSelect and explain. \nA. Lumbar vertebra, B. Cervical, C. Thoracic, D. Sacral', 'role': 'user'}, {'content': 'Answer: C \nExplanation: ANSWER: (C) ThoracicREF: Tuberculosis of skeletol system SM tuli 3rd e p, 192Important points about skeletal TBMost commonSite: vertebralSite in vertebra: lowerthoracic or dorsolumbar Route of spread: hematogenousType: paradiscalSymptom: back pain', 'role': 'assistant'}]