Answer:
The main ideology in the US is that the power is in the people, competition is encouraged, and people can own land as long as they have money. The main ideology in the Soviet Union is that the power is in the government, everyone gets a certain amount of food, land, money no matter how much money they have and are usually under strict control. Basically the main difference is the US claims to have everyone equal and the Soviet Union makes everyone equal (except for the government).
there ya go hope this helped
Image result for which is an example of limited power in the united states
The Bill of Rights holds many examples of Limited Government. For example, American citizens have the right to free speech, to protest, and the government cannot come to your house and search without a warrant. Another example is checks and balances and the separation of powers set up in the United States government.
It's not A because Lewis and Clark explored it.
I'm pretty sure the answer is D. from what I've researched the lands were really hard to farm on that the government had to pass a Homestead Act to get people to settle there.