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': 'Sine wave pattern in E.C.G is seen in- \nSelect and explain. \nA. Hypokalemia, B. Hyperkalemia, C. Hyponatremia, D. Hypermatremia', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Classically, the electrocardiographic manifestations in hyperkalemia progress from tall peaked T waves (5.5-6.5 mM), to a loss of P waves (6.5-7.5 mM) to a widened QRS complex (7.0-8.0 mM), and, ultimately, a to a sine wave pattern (>8.0 mM). REF: HARRISON, 19e, Pg 310', 'role': 'assistant'}]