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': 'Gray equals \nSelect and explain. \nA. 100 rad, B. 1000 rad, C. 10000 rad, D. All', 'role': 'user'}, {'content': 'Answer: A \nExplanation: A i.e., 100 rads Rad (radiation absorbed dose) is energy deposited within living matter & is equal to 100 ergs/gm of tissue. Whereas, I gray is absorption of 1 joule energy by 1 kg living matter.', 'role': 'assistant'}]