When a beam of white light passes through a glass prism, it undergoes refraction, or the bending of light, which causes the different colors within the white light to separate. This separation is known as dispersion.

The amount of bending, or deviation, experienced by each color of light depends on the wavelength of the light. The longer the wavelength, the less the deviation and vice versa. In other words, the light with the shorter wavelength experiences a greater deviation compared to the light with a longer wavelength.

In the case of the question, the color of light that deviates the least is red. Red light has a longer wavelength compared to the other colors, such as blue, green, and violet. Therefore, it experiences the least amount of bending or deviation when passing through the prism.

It is important to note that, in general, the colors with shorter wavelengths, such as blue and violet, experience greater deviation, while the colors with longer wavelengths, such as red, deviate the least.

Therefore, option 2, which states that the color of light that deviates the least is red, is the correct answer.