The visible light microspectrophotometer is a convenient tool with which to compare the color of fibers because:
a. very small samples can be compared
b. fibers can be studied right on a microscope slide
c. fibers are not destroyed
d. all of the above

d. All of the above

Explanation:

A microspectrophotometer is an instrument used to measure the spectra of microscopic samples, thus,  it is used for color comparison between samples.

It  is able to measure very small samples , as small as  1 x 1 micrometers. That is, smaller than the diameter of a human hair, therefore it is suitable for the analysis of many other types of fibers that can be mounted on  microscope slides.

The microspectrophotometer allows to acquire extremely small sample spectra without destroying them at all

i think the answer is composed of atoms