This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pathology
[{'content': 'A pt of BPD on lithilhium for 6months after fasting for a day presents with seizure coarse tremors confusion and weakness of limbs Whats the most accurate to diagnosis her condition \nSelect and explain. \nA. Serum Electrolyte, B. s.Lithium, C. S .creatinine, D. ECG', 'role': 'user'}, {'content': 'Answer: B \nExplanation: ref : harissons 21st ed', 'role': 'assistant'}]