The question is incomplete. No options are given (for which of the following) to answer the question.
The Northwest Ordinance of 1787
farmland and space
The Appalachian Mountains provided a natural barrier to the western expansion of the English Colonies in America, or so some thought.
The Homestead Act of 1862.
Marshall plan
The lend-lease act.
The Marshall Plan ,
the marshall plan The policy is called the Marshall Plan.
Marshall Plan
Marshal plan
The Lend-Lease Act of March 11, 1941, enabled America to directly aid Britain and her Allies during the WW II.
The Marshall Plan
The Marshall Plan or officially the European Recovery Program (ERP). It was funded by President Harry Truman in April of 1948. The plan was named after the man that offered up the concept, George C. Marshall, Truman's Secretary of State.
Northwest Ordinance
A continuous airlift of goods from Western Germany to Berlin.
Provided funding for the economic reconstruction of Western Europe.