This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Fluid and electrolytes, Subject name: Medicine
[{'content': 'In hyponatremia following renal failure, serum sodium should be maintained at what levels ? \nSelect and explain. \nA. 120 mEq/L, B. 125 mEq/L, C. 130 mEq/L, D. 135 mEq/L', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Hyponatremia in CKD population is associated with increased moality, but the effect on renal outcome was unknown.. Hyponatremia (serum sodium <120 mEq/L) was associated with excessive volume and volume depletion, measured as total body water by bioimpedance analysis, in diuretic users, but not in diuretic non-users Ref Davidson 23rd edition pg 366', 'role': 'assistant'}]