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: Surgery
[{'content': 'In the immediate post operative period, body potassium is: \nSelect and explain. \nA. Exchanged with calcium, B. Exchanged with magnesium, C. Retained in body, D. Excreted excessively', 'role': 'user'}, {'content': 'Answer: D \nExplanation: In immediate post-operative period, due to increased adrenocortical activity, there is Na+ retention and K+ excretion.', 'role': 'assistant'}]