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': 'X-ray was discovered by Roentgen in: \nSelect and explain. \nA. 1886, B. 1902, C. 1895, D. 1907', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. 1895', 'role': 'assistant'}]