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': 'Tardy ulnar neuritis may be due to \nSelect and explain. \nA. Advanced osteo ahritis of elbow, B. Cubitus valgus deformity, C. Both of the above, D. None of the above', 'role': 'user'}, {'content': 'Answer: B \nExplanation: B i.e. Cubitus valgus deformity', 'role': 'assistant'}]