Which kinds of buttons are sewn onto northwest coast button blankets?

a.
stone

b.
animal bone

c.
plastic

d.
shell

(D) shell is the correct answer.

Explanation:

A button blanket is a blanket that is created and worn by the North Coastal Tribes.  It is mostly worn for ceremonial purposes. It is one of the most spectacular creations of the Indian people of the Northwestern Coast. The robes served as a clans insignia of family and clan histories, rights and privileges. these robes are used as capes and gifts at ceremonies. The blankets were first acquired by the Hudson Bay Company traders. Those blankets were dark blue and were decorated with the buttons which were made of dentalium. The wearer's family heritage was portrayed on the central crest. They also had a red border on the edges.

the idealization of the rural landscape ; admiration for the beauty of nature ; focus on an individual's inner concerns