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': 'Blood buffers are: \nSelect and explain. \nA. Bicarbonate, B. Plasma proteins, C. Hemoglobin, D. All', 'role': 'user'}, {'content': 'Answer: D \nExplanation: A i.e. Bicarbone; B i.e. Plasma Proteins; C i.e.Hemoglobin', 'role': 'assistant'}]