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: Psychiatry
[{'content': 'Prophylactic maintenance serum level of lithium is : \nSelect and explain. \nA. 0.5 - 0.8 mEq/L, B. 0.7 - 1.2 meq/L, C. 1.2 - 2.0 meq/L, D. 2.0 - 2.5 meq/L', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Blood lithium levels\xa0:\n\nTherapeutic level\xa0:\xa00.8 - 1.2 mEq/L.\n\n(For t/t of acute mania)\n\nProphylactic level\xa0:\xa00.5 - 0.8 mEq/L.\n\n\xa0 \xa0 \xa0 \xa0 \xa0\xa0\xa0(For relapse prevention in bipolar disorder)\n\nToxic lithium levels\xa0: > 2.0 mEq/L.', 'role': 'assistant'}]