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: Physiology
[{'content': 'Largest fraction of CO2 is present in blood as \nSelect and explain. \nA. Attached with RBC, B. Dissolved in blood, C. Wth Hb as carbaminohemoglobin, D. Bicarbonate', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]