<prompt> Prions are killed by:AutoclaveEthylene dioxideGamma radiationAutoclave and NaOH  <response>: Ans. is d i.e., Autoclave and NaOHPrions can be destroyed by one of these four options:Option 1. Autoclave at 134degC for 18 minutes in a prevacuum sterilizer.Option 2. Autoclave at 132degC for 1 hour in a gravity displacement sterilizer.Option 3. Immerse in 1NNaOH1NaOHis a solution of 40gNaOH 1Lwater for 1 hour; remove and rinse in water, then transfer to an open pan and autoclave 121 degC gravity displacement sterilizer or 134degC porous prevacuum sterilizer for 1 hour.Option 4. Immerse in 1NNaOHfor 1 hour and heat in a gravity displacement sterilizer at 121degC for 30 minutes, then clean and subject to routine sterilization. 