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: Gynaecology & Obstetrics
[{'content': 'Maximum permissible radiation dose in pregnancy is : \nSelect and explain. \nA. 0.5 rad, B. 1.0 rad, C. 1.5 rad, D. 5.0 rad', 'role': 'user'}, {'content': 'Answer: D \nExplanation: 5.0 rad', 'role': 'assistant'}]