Answer:
Violet
Step-by-step explanation:
The visible spectrum of EM spectrum composed of mainly seven colors that possess different wavelengths. It is called visible spectrum because it is only part of EM spectrum that can be seen by the human eyes.
These colors from longest to shortest wave length can be written as red, orange, yellow, green, blue, indigo, and violet. Thus , we can say that violet color is color with least wavelength.