Which nation most prospered from the lands of Oklahoma?

A) Spain

B) France

C) England

D) United States

United States

Explanation:

The region of Oklahoma was Indian territory until the second half of 19th Century. Then in the 1880s pressure for the white settlement of Oklahoma started. In 1890 it was incorporated into United States.

Economical prosperity for the States in here started in 1973., when the energy boom in here was started. All other mentioned country had nothing to do with Oklahoma.

Answer: The United States