Answer:
C
Explanation:
Today, McCarthyism refers to a "witch-hunt" as Senator McCarthy led a witch hunt against purported communists in the US.
Appropriate level of formality
It was before the era of railways hence waterways were critical factor. They determined the population centers access to trade. Examples rivers (New Orleans, Cincinnati), Great Lakes (Chicago, Detroit), canals (Milwaukee) and obviously sea port cities (New York)
I think the answer would be 7. c: