consider the colors of the visible light spectrum. which of the color has the lowest frequency
This distribution covers a vast range of frequencies and wavelenghts, and it is divided into subranges (portions of the EM spectrum). The order of these subranges - either from lowest to highest frequency, or from longest to shortest wavelenght - is: Radio, Microwave, Infrared, Visible, Ultraviolet, X-Ray, and Gamma Ray. So, for the visible range, the colors are arranged in order of increasing frequency like this: Red < Orange < Yellow < Green < Blue < Indigo < VIolet. Here are a picture of the EM spectrum with emphasis on the visible range : and a picture that depicts the frequencies associated with each color.