Of the electromagnetic radiation forms, which has the lowest energy and which has the highest?

In the context of electromagnetic radiation, energy is directly related to the frequency and inversely related to the wavelength. As the frequency increases, so does the energy of the radiation.

Radio waves are at the lower end of the electromagnetic spectrum, characterized by their long wavelengths and low frequencies, which results in them having the lowest energy among the various forms of electromagnetic radiation. This makes them appropriate for applications like communication over long distances.

On the opposite end, gamma rays possess very short wavelengths and extremely high frequencies, leading to their classification as the highest energy form of electromagnetic radiation. They are known for their use in medical treatments and in the detection of certain types of radiation, given their ability to penetrate materials.

The combination of radio waves having the lowest energy and gamma rays having the highest energy establishes option D as the correct choice for this question.