What central idea is conveyed about minorities and the parts they played in the settling of the american west?

Some minoritiy groups who played a role in the American settling in the West is African-Americans, Mexicans and Asians, for example.

African-Americans, Mexicans and Asians were the other faces of the American West. They were everything a person could be at the time. From cowboys, explorers, miners, scouts, outlaws and lawmen, they played a huge part in the West.

The central idea is that the West, as well as America as a whole, was built upon diversity, and cooperation, regardless of where you come from and the color of your skin. Minorities have always been and will always be there, no matter the time and how big the role, but they're part of every story.

i am sure the answer is d