Answer:
Popular sovereignty, also called squatter sovereignty, in U.S. history, a controversial political doctrine according to which the people of federal territories should decide for themselves whether their territories would enter the Union as free or slave states.
Explanation:
May be D. the 13th Amendment was passed.
Wester economies became stronger after the Marshal Plan was put in place because the U.S. pumped $13 billion into European economy.
In a closed primary election only those from the same party may vote in the primary. Democrats can only vote in the democratic primary while Republicans vote in their primary. In a open primary anyone can vote in the primary of either party without concern of which political party they are registered as.