Which source of radiation exposure is related to the use of medical imaging?

• A. Terrestrial
• B. Internal
• C. Manmade (artificial)
• D. Cosmic

Answer: (C)

Medical imaging relies on radiation produced by human-made devices or substances, such as X‑ray tubes in radiography and CT, or radiopharmaceuticals used in nuclear medicine. Because imaging uses energy generated or supplied by humans, the exposure is considered manmade (artificial). In contrast, terrestrial exposure comes from naturally occurring materials in soil and rocks, cosmic exposure from space radiation, and internal exposure from radionuclides already inside the body. So the radiation exposure related to medical imaging is a manmade source.