The depiction of the battle of Sioux in 1797 on a Mandan robe is made using a buffalo robe. This buffalo robe is a cured buffalo hide with the hair still left on. The paint used on the buffalo hide are made from natural pigments. The hide is tanned and painted afterwards.
These indentations are called coffers.
When you are talking to someone and you want a certain phrase you said to stand out, you emphasis your words. That is pretty much the same case here. A is incorrect because that is capturing a model of some sort, B is incorrect because that would be an equal blend of all colors together, and D is incorrect because you are not uniting the colors, you want the elements to stand out. Emphasis is achieved usually by using mostly dark colors then a splash of something such as neon pink or yellow.
