A spectrograph is used to:

A: see radio waves
B: analyze infrared and ultraviolet rays
C: measure distance
D: photograph the light spectrum

the answer is D because it gets the spectrum of light

myth. it was once thought that animals, including cats and dogs, could only see in black and white. however, scientists have proven this to be a myth. in all animals, including humans, the perception of colour is determined by the presence of cells in the eye called cone photoreceptors.