Marshall Plan
The "Marshall Plan" was named after the man who then was US Secretary of State, George C. Marshall. Officially the plan was called the European Recovery Program. Marshall announced the plan in 1947, and it went into effect in 1948. The intent was to provide aid and rebuilding to European economies after the damaging effects of World War II. The US intended to build up its allies in Europe and stave off communism.
The Ohio River Valley was fought over for resources that were good for trade such as fur. The French and British were fighting over power and resources during this time. French had colonized lands to the West while the British colonized lands on the East Coast of North America. They had a border dispute as to who owned the land in the Ohio River Valley, and the French and Indian War break out.
I would go with C cause its the only one that would go along the lines of buying or selling