This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General Microbiology Pa-2 and Pa-3 (Sterilization and Bacterial Genetics), Subject name: Microbiology
[{'content': 'The biological indicator used in various autoclave machines for quality check is- \nSelect and explain. \nA. Clostridium tetani, B. Bacillus stereothermophilus, C. Bacillus pumilus, D. Bacillus subtilis', 'role': 'user'}, {'content': 'Answer: B \nExplanation: METHOD Sterlization control Hot air oven Autoclave Filtration Ionizing radiation (cold sterilization) Ethylene oxide Plasma sterilization Clostridium tetani non toxigenic strain, B.subtilis sub sp. niger B.Stearothermophillus Brivundimonas dimunata B. Pumilus B.Globigi B.Stearothermophillus', 'role': 'assistant'}]