Answer:
Jacinda went to Comic Con in hopes of meeting all her favorite heroes: Dr. Who, The Green Arrow, The Black Canary, and Supergirl.
Explanation:
A colon (:) is used to introduce or announce a phrase, quotation, or even list a noun or a number of elements. In other words, a colon is used to separate two independent clauses where the second explains the first.
In the given sentence, the correct usage of the colon is in sentence 4. This is because the colon is used to list the "favorite heroes" of Jacinda. And to list the four heroes, the colon introduces and lists them, with a period in between.
Thus, the correct answer is
<u><em>Jacinda went to Comic-Con in hopes of meeting all her favorite heroes: Dr. Who, The Green Arrow, The Black Canary, and Supergirl.</em></u>
