The energy of a photon is inversely proportional to its wavelength (E = hc/λ, where h is Planck's constant, c is the speed of light, and λ is wavelength). This means that shorter wavelengths correspond to higher photon energies. Comparing the given ranges: - A) 320 – 400 nm (UV-A / lower visible) - B) 200 – 280 nm (UV-C) - C) 280 – 320 nm (UV-B) - D) 400 – 600 nm (Visible light) The range 200 – 280 nm has the shortest wavelengths, and therefore the highest energy per quantum (photon). This range corresponds to UV-C radiation, which is the most energetic and potentially harmful part of ultraviolet light, though most of it is absorbed by the Earth's atmosphere.