Which of the following is a source of man-made radiation?

Tanning beds are classified as a source of man-made radiation because they emit ultraviolet (UV) radiation, which is intentionally produced by the devices for the purpose of tanning. This artificial source of radiation is distinct from natural sources, which include cosmic radiation or radon gas found in the environment.

Man-made radiation sources also encompass various medical imaging techniques, industrial applications, and consumer products that utilize radiation. In this context, tanning beds are specifically designed to deliver UV radiation to users, making them a clear example of how human intervention creates radiation exposure.

In contrast, sunlight is a natural source of radiation, as it comes from the sun's natural processes. Radon gas is a naturally occurring radioactive gas that comes from the decay of uranium in soil and rocks. Natural background radiation consists of various forms of radiation present in our environment, which are not influenced by human activity. These distinctions highlight the unique status of tanning beds as a man-made source of radiation.