Correct Option: A

The electromagnetic spectrum is the name we use when we talk about different types of radiation as a group. The parts of the electromagnetic spectrum, arranged from highest energy to lowest, are gamma rays, X-rays, ultraviolet light, visible light, infrared light, microwaves, and radio waves. All the parts of the electromagnetic spectrum are the same thing — radiation. Radiation is made up of a stream of photons — particles without mass that move in a wave pattern, all at the same speed — the speed of light. Each photon contains a certain amount of energy. The only difference between the parts of the electromagnetic spectrum is the amount of energy the photons contain. Radio waves have the least energy, and gamma rays have the most