This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Fundamentals In Radiology, Subject name: Radiology
[{'content': 'Hounsfield units are used in CT density scale to measure attenuation value of different materials compared to water. The value of fat in HU would be around: \nSelect and explain. \nA. -100, B. -1000, C. 100, D. 1000', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. A. -100The value of fat is around -100HU.In a CT density scale* Air = -1000 (Black)* Fat = -100* Water = 0* Concealed blood =+60 to+70* Calcification =+1000 (White)', 'role': 'assistant'}]