This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Environment and health, Subject name: Social & Preventive Medicine
[{'content': 'The permissible dose of radiation from man sources in terms of rads per year should not exceed - \nSelect and explain. \nA. 1, B. 5, C. 10, D. 15', 'role': 'user'}, {'content': "Answer: B \nExplanation: Park's textbook of preventive and social medicine 23rd edition. * The additional permissible dose from man made sources should not exceed 5 rad a year.", 'role': 'assistant'}]