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': 'SI unit of radiation absorbed dose is \nSelect and explain. \nA. Rem, B. Gray, C. Rad, D. C/kg', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Absorbed dose - Gray (SI)\nExposure dose - C/kg (SI)\nDose equivalent - Sievert', 'role': 'assistant'}]