Which color of light is refracted the least when passing through a prism?

When light passes through a prism, it undergoes a phenomenon known as refraction, which causes it to bend. The degree to which light is refracted depends on its wavelength; shorter wavelengths are refracted more than longer wavelengths.

Red light has a longer wavelength compared to other colors in the visible spectrum, such as blue, green, and yellow. Because of this longer wavelength, red light is refracted the least when it enters and exits a prism. In contrast, blue light, which has a shorter wavelength, bends more sharply and is refracted significantly more.

Thus, when considering the colors of light mentioned, red least refracts in a prism, making it the correct choice for this question.