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: Radiology
[{'content': 'Amount of X-rays that undergo Compton scattering: \nSelect and explain. \nA. 7%, B. 23%, C. 57%, D. 70%', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]