Question

In order to change the color of light you must change

Only the frequency of the light
Only the wavelength of the light
Either the frequency or the wavelength of the light
Neither the frequency nor the wavelength of the light

Answer 1

I'd say neither the frequency nor the wavelength of the light due to there not being an initial color. Also, the wavelength would not play a part in color change. Help?

Answer 2

Yeah :)

Answer 3

the colour of light depends on its frequency

however, if you change the wavelength, you can argue that that involves changing the frequency also as light travels at the speed of light ... so the question is ambiguous.

however, on the basis that you can change the wavelength of light by refraction, say, without changing its frequency [ because its speed also changes], i'd go with A.