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': 'Stress fracture is treated by: \nSelect and explain. \nA. Rest, B. Cast immobilization, C. Closed reduction, D. Internal fixation', 'role': 'user'}, {'content': 'Answer: B \nExplanation: B i.e. Cast immobilization', 'role': 'assistant'}]