Answer:
Gamma rays
Step-by-step explanation:
The electromagnetic spectrum classifies all the different types of electromagnetic radiation based on their wavelength.
In increasing order of wavelength, they are the following:
Gamma rays
X-rays
Ultraviolet
Visible light
Infrared radiation
Microwaves
Radio waves
Therefore, gamma rays are the electromagnetic waves with shortest wavelength, while radio waves are those with longest wavelength. Based on this order, we also notice that X-rays are the nearest to the gamma rays, since they have wavelength just a bit longer than gamma rays.
Therefore, the correct answer is gamma rays.