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': 'Which is used in teletheraphy & Brachytherapy both – \nSelect and explain. \nA. Iridium 127, B. Cobalt 60, C. Pallidium, D. Iodine 131', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Co - 60 and Cs - 137 are used both in teletherapy and brachytherapy', 'role': 'assistant'}]