Sentence 4 is the one that uses the correct format for a parenthetical citation.
Parenthetical citation is used in an essay or a paper in order<u> to indicate that the information presented comes from another source</u>. It works as a way of giving credit to the real author. Furthermore, in a parenthetical citation,<u> both the author and page number are cited in parentheses and always in that order</u>. <u>Sentence 4</u> is the correct option since it is the only one that <u>provides first the author and then the page number in parentheses</u>.
