Radioactivity's role in hospital procedures

Steps:

• List hospital activities involving radioactivity: diagnosis (e.g., scans), treatment (e.g., radiation therapy), and sterilization (e.g., irradiation).
• Check each option against these uses.
• Note that cooking uses heat, not radiation.
• Confirm A as the outlier with no radioactive link.

Why A is correct:

• Cooking meals uses thermal processes like boiling or baking, defined by heat transfer, not radioactive decay or ionizing radiation.

Why the others are wrong:

• B: Gamma rays from radioactive isotopes like cobalt-60 sterilize equipment by killing microbes.
• C: Radioactive tracers in imaging like X-rays or PET scans diagnose illnesses by detecting emissions.
• D: Radiotherapy employs radioactive sources or beams to target and destroy diseased cells.

Final answer: A