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': 'March fracture is fracture of: September 2007 \nSelect and explain. \nA. Calcaneus, B. 2nd metatarsal, C. Distal fibula, D. Proximal tibia', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. B: 2nd metatarsal A stress fracture of the 2nd or 3rd metatarsal bone is sometimes called a 'march fracture' because soldiers running in boots often get it. The fracture heals spontaneously, so treatment is purely symptomatic.", 'role': 'assistant'}]