Correct Answer:
B. Gamma rays
The electromagnetic spectrum arranges different types of radiation by wavelength and energy. There is an inverse relationship between wavelength and energy: shorter wavelengths correspond to higher energy. Among the given options, Gamma rays (Option B) are at the highest energy and shortest wavelength end of the electromagnetic spectrum. Ultraviolet rays (Option A) have higher energy than visible light but less than X-rays and gamma rays. X-rays (Option C) have higher energy than UV rays but less than gamma rays. Therefore, gamma rays possess the shortest wavelength and highest energy.