I think that it's D because it makes the most sense
Having a Cultural diverse space in the United States can help us interact with others to build trust, understanding and respect to other cultures. Having a diverse and inclusive community helps with preventing more personal biases, negative stereotypes, racism and bigotry from occurring. It also helps build a more safer and stronger community.
Coastal plains and Interior plains is in elevation. Coastal plains have low elevation and low relief. Interior plains have varied elevation and low relief. Coastal plains also lie along the shore while Interior plains are surrounded by other hopefully this helps
