Answer : The correct option is, (c) ionizing radiation
Explanation :
Ionizing radiation : it is defined as the energy that is released by the atoms which travels in the form of electromagnetic waves or particles.
The electromagnetic waves are gamma-ray, X-rays, U.V rays, infrared ray, microwave and radio-wave.
The electromagnetic particles are alpha, beta and neutrons.
Isotope : It is defined as the element that have the same number of protons but have the different number of neutrons of each of the atom.
Hence, the alpha and beta particles and gamma rays are examples of ionizing radiation.