Answer: The answer is "C"
Step-by-step explanation:
The electromagnetic waves are arranged in the increasing wavelength and energy by the following order;
Radio waves has the lowest energy and wavelength but of the highest frequency.
The Infra-red rays follows the visible light follows, the ultraviolet ray follows, the X-ray follows and then the Gamma-ray has the highest energy and wavelength but the lowest frequency.
Therefore the answer is C, radio, infra, visible, ultraviolet, x-ray, gamma.