The correct answer to this question is- B) Red, orange, yellow, green, blue, indigo, and violet.

EXPLANATION:

The visible region of the electromagnetic spectrum consists of white light with its constituent seven colors.

The constituent colors are known as violet, indigo, blue, green, yellow, orange and red respectively.

As per electromagnetic spectrum, these colors of light lie in the wavelength region ranging from 350 nm to 700 nm.

The wavelength of violet light is minimum, and is maximum for red light.

If we arrange these seven colors in the descending order of their wavelength, then they are arranged as follows-

      Red > Orange > Yellow > Green > Blue > Indigo > Violet.

Hence, the perfect order is option B .