An armistice is an agreement between warring parties to stop fighting.
I believe the answer is C.
The entry of the US into WWI really boosted the Allied Powers' morale, while destroying the morale of the Central Powers.
While the rest of the Allies had been fighting for nearly four years at this point, when the US entered, they were fresh, energized, and idealistic.
Basically, US soldiers encouraged the other Allies and helped them get their mojo back.
The correct answer is: D. a program to aid European nations to promote prosperity and democracy
The Marshall Plan was an economic aid package that was put forward to work and bring European nations hurting after World War II into the United States' sphere of influence and away from the influence of the Soviet Union.
John Brown stirred up a lot of controversy with his attack on "Harper's" Ferry in Virginia, since this was a raid aimed at arming slaves and freedman alike in order to inspire a massive revolt.
