The task completed with infrared radiation is removing bacteria from the air in hospitals. Infrared radiation can be used in various disinfection methods, such as infrared heaters or devices that use infrared light to kill bacteria and viruses in the air.
The other options primarily involve different types of radiation or methods (e.g., X-rays for diagnosing broken bones or decayed teeth, radio waves for cell phone communication, and light transmission in fiber optic cables).