From the mid-1930s to 1940 over 2.5 million people had moved out of the great plains states in the center of the united states. what best accounts for this movement?

It was the  Dust Bowl. The dust storms extremely affected the agriculture negatively.  

d. all of the above is the correct answer here. socialism is the antithesis of capitalism, and uses a command economy and government controlled production.

sola scriptura

sola fide

sola gratia

solus christus or solo christo

soli deo gloria