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': 'Pattern theory of pain control was given by \nSelect and explain. \nA. Von frey, B. Melzack, C. Goldschneider, D. Descartes', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]