I'm pretty sure the answer is Ostrich Eggs
B.
it cannot be A because many masks are symbols of fertility that are used in the honorary ritual of woman which does not include channeling spirits
it cannot be C because you think about the cave paintings that are primarily 2D
I believe the answer is, actually, D. The red will be too exciting and distracting to the calm library.
If you research the library, it is actually quite a colourful place, but the red on the inside, as well as the outside, would have been too much and indeed; distracting and exciting.
