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: Dental
[{'content': 'X-rays were discovered by \nSelect and explain. \nA. Madam curie, B. Roentgen, C. Rutherford, D. Becquerel', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]