This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Environment and Health, Subject name: Social & Preventive Medicine
[{'content': 'Autoclaving is not useful for disposal of: \nSelect and explain. \nA. Surgical dressings, B. Metallic instruments, C. Petri dishes, D. Liquid paraffin', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. (d) Liquid paraffinRef : K. Park 23rd ed. /128* Autoclaving is a method of disinfection mainly used for surgical dressings, instruments, laboratory wares, media and pharmaceutical products.* Principle: Steam + High pressure (~ 30 psi) and temperature 121 C.* Efficiency test of autoclaving: spores of Bacillus Stearothermophillus.', 'role': 'assistant'}]