A 28-year-old male laboratory technician at a government medical college in Mumbai is tasked with sterilizing reusable surgical instruments for the operation theatre. He has access to an autoclave, ethylene oxide gas sterilizer, and a dry heat oven. The instruments include stainless steel forceps, rubber gloves, and plastic syringes. He must choose the most appropriate sterilization method that will effectively sterilize all these items without causing material damage. Which sterilization method should he select?