What type of sterilisation is achieved through the use of ethylene oxide?

Ethylene oxide is a gaseous chemical agent used for sterilization, making chemical sterilization the correct choice. This method is especially useful for heat-sensitive materials that cannot withstand high temperatures involved in heat sterilization processes like autoclaving. Ethylene oxide works by disrupting the DNA of microorganisms, leading to their inability to reproduce and effectively killing them.

This type of sterilization is commonly used for medical equipment, particularly in the healthcare industry, where certain instruments, such as those made of plastics or other sensitive materials, require a non-heat method of sterilization to maintain their integrity and functionality.

The other methods mentioned, such as heat sterilization, radiation sterilization, and filtration, are different processes involving either temperature, high-energy radiation, or physical removal of microorganisms, respectively, and are not applicable in the context of ethylene oxide, which relies purely on its chemical properties to achieve sterilization.