Which of the following is a type of electromagnetic radiation that is generated nonradioactively?

• A. Alpha particles
• B. Beta particles
• C. Gamma radiation
• D. X-rays

Answer: (D)

Electromagnetic radiation comes from photons, and the way these photons are produced matters. Gamma rays are typically emitted by atomic nuclei during radioactive processes, so they are closely tied to radioactivity. X-rays, on the other hand, can be generated by nonradioactive means—such as electrons accelerated in an X-ray tube or other non-nuclear interactions—so they don’t require radioactive materials to be produced. Alpha and beta refer to particles, not electromagnetic radiation, so they aren’t the type in question. Therefore, X-rays are the type of electromagnetic radiation that can be generated without radioactivity.