Steam under pressure for instrument sterilization is...

Ultrasound refers to sound waves above the audible range, commonly used in imaging and cleaning processes, but it does not involve the use of steam or pressure for sterilization. While ultrasonic cleaning can remove debris from instruments, it does not achieve the high sterilization standards that autoclaving does.

Scrubbing involves manually cleaning instruments to remove visible contaminants and debris but does not guarantee sterilization. While it is an essential step in the cleaning process, it lacks the capability to eliminate all microorganisms, particularly resistant spores, making it insufficient as a standalone sterilization method.

Sanitization refers to reducing the number of microorganisms to safe levels, typically through cleaning and disinfection processes. However, it does not equate to sterilization, which requires the complete eradication of all microbial life, including resistant spores. Therefore, sanitization is less comprehensive than the sterilization achieved by an autoclave.