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': 'In a modern rotatory anode X-ray tube cooling of anode is done by: \nSelect and explain. \nA. Conduction, B. Convection, C. Radiation, D. All of the above', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. Radiation', 'role': 'assistant'}]