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: Microbiology
[{'content': "Metachromatic granules are stained by- \nSelect and explain. \nA. Ponder's stain, B. Negative stain, C. Gram stain, D. Leishman stain", 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]