This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Normal Physiology - Sodium, Potassium, and Acid-Base Balance, Subject name: Surgery
[{'content': 'Concentration of Na (mEq/I) in normal saline is? \nSelect and explain. \nA. 77, B. 109, C. 130, D. 154', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. (d) 154Ref: Essentials of General Surgery edited by Richard M. Belly Merril T. Dayton p-51 4thed', 'role': 'assistant'}]