B. The Manhattan Project. and the location (Los Alamos NM) was referred to as the Manhattan engineering district
It was "a. South Carolina" that defeated the cooperationist argument that the South should act as a unit, since it was South Carolina that was the first to officially secede from the Union.
The turning point of the American Revolution occurred at the battle of "Saratoga," due mostly to the fact that the the colonial victory of Britain convinced the French to officially support the colonial army against the British.