Answer:
4. All of these.
Explanation:
1.The elements are placed in special cameras which record images from emitted radiation, like x-ray equipment. This is correct statement regarding radioactive elements used for medical diagnosis.
2.Some isotopes are absorbed in particular tissues and organs. Carbon Isotope that is C-14 are by every living being.
3.These radioactive isotopes act as tracers. The radiation from certain elements can penetrate the entire body and expose all internal organs to photographic film. This statement is correct too because we Radioactive isotope of Iodine that is [tex]I_{131}[/tex] to determine the activity of thyroid gland.
Hence all the above statement are true.
4. All of these.
