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: Medicine
[{'content': 'Sustained diarrhoea can lead to \nSelect and explain. \nA. Metabolic Acidosis, B. Metabolic Alkalosis, C. Respiratory Alkalosis, D. Respiratory Acidosis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]