What are the "these" you speak of?
Although there definitely existed "robber barons" who took advantage of a delicate and changing situation, most of these men were mostly well-meaning people who wanted to capitalize on an opportunity, and whose actions increased the welfare of many Americans.
The last choice “were formed by outside conquerors who unified the regions they conquered through their use of military technology”
Parenthetical citations reference the original sources that are used in an essay or paper. <u>It immediately tells the reader where your data is coming from, and shourtcuts the unnecessary trouble of having to make footnotes</u>.
For print sources like books, magazines, <u>or the encyclopidia given in your example</u>, you have to provide the author's last name and the page number in the source material from where your citation comes from.
It would look like this: "After the Civil War, the amount of counterfeit money in circulation was a big problem for the government" (Ray 34).
When it comes to electronic sources, the absence of page numbers should not be a problem in creating parenthetical citations. All you have to do is provide the author's or article's name; and unless you must list the website's URL to give the reader a direct entry to the page, do not include entire URLs in the text. Instead, provide partial URLs like the name of the website or its domain.
In this case, your example would look like this: "After the Civil War, the amount of counterfeit money in circulation was a big problem for the government" (Know Your Money, Secretservice.gov).
Hope this helps!