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': '40 % formalin is used to sterilize - \nSelect and explain. \nA. Plastic syringes, B. All microbes + spores, C. Clothes, D. Stitches', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]