This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Medicine
[{'content': 'Tall T wave in E.C.G occurs in - \nSelect and explain. \nA. Hyperkalemia, B. Hypokalemia, C. Hypercalcemia, D. Hypocalcemia', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Tall T waves are a feature of hyperkalemia ref Harrison 20th edition pg 1554', 'role': 'assistant'}]