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: Physiology
[{'content': 'The most common electrolyte disorder encountered in clinical practice \nSelect and explain. \nA. Hyponatremia, B. Hypocalcemia, C. Hypernatremia, D. Hypokalemia', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Hyponatremia is the most common electrolyte disorder encountered in clinical practice and may occur in up to 15% to 25% of hospitalized patients.', 'role': 'assistant'}]