Answer;
Gamma rays
Gamma rays are the radioactive emissions with the most penetrating power.
Explanation;
- Alpha, beta particles and gamma rays are the three main types of radiations emitted by unstable or radioactive isotopes.
- Gamma radiation does not consist any particles but contain a photon of energy emitted from an unstable nucleus. Gamma radiation has no charge or mass, thus can travel farther through air than the other radiations.
- Gamma is the most penetrating radiation with alpha being the least penetrating.