Which of the following sentences requires citation?
A.
At our school, we only learned about a fraction of the political and economic complexities of the American Civil War.
B.
I would wager that most students in the United States will be able to tell you that the Battle of Fort Sumter in 1861 started the American Civil War.
C.
There were buffalo in every western territory of the United States as of 1860.
D.
They say that history is written by the victors.
The sentence that requires a citation is:
C. There were buffalo in every western territory of the United States as of 1860.
This statement presents a factual claim about historical conditions and would need a citation to back up the information. The other sentences are either general observations, personal opinions, or widely recognized phrases that typically do not require citations.