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': 'Oil and grease are sterilised by-( \nSelect and explain. \nA. Hot air oven, B. Autoclaving, C. Filtration, D. Irradiation', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Hot air oven", 'role': 'assistant'}]