The tenth amendment was added to the bill of rights because the framers believed in the principle of: giving all power to a central government. controlling civil liberties. establishing federalism. limiting citizen’s rights.

The correct option is:  establishing federalism.

The Tenth Amendment to the Constitution of the United States, also called the Tenth Amendment ('Amendment X), is part of the declaration of rights that was ratified on December 15, 1791. The tenth amendment to the constitution says that' The powers that be the Constitution does not delegate to the United States or prohibit the States, it is reserved to the States respectively or to the people.

not sure might be he acquired the entire oregon territory from great britain