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': 'Normal anion gap is (in mEq/L) ? \nSelect and explain. \nA. 5-Mar, B. 12-Oct, C. 18-20, D. 25-30', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is `b' i.e., 10-12", 'role': 'assistant'}]