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': 'Mathematical representation of inverse square law is \nSelect and explain. \nA. I2/I1 = (D2)2 / (D1)2, B. I1/I2 = (D2)2 / (D1)2, C. I2/I1 = (D2) / (D1), D. I1/I2 = (D2) / (D1)', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]