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': 'Least common complication of closed supracondylar fracture in a 8 year old child is: \nSelect and explain. \nA. Cubitus valgus, B. Cubitus varus, C. Nonunion, D. Vessel injury', 'role': 'user'}, {'content': 'Answer: C \nExplanation: C i.e. Nonunion', 'role': 'assistant'}]