You can introduce a quotation with a if the words before the quotation are a complete sentence.
a. blank line
b. comma splice
c. colon
d. semi-colon

The correct answer is C. Colon

Explanation:

In writing, a quotation occurs when the author of a text quotes or uses the exact word of an external source and author to reinforce or explain his/her own ideas. In terms of style, quotations should always be marked by quotation marks (") and information about the author of the quotation should be included following manual styles. Additionally, quotations can be placed in the text without any preceding punctuation mark or introduced by a colon (:); however, the colon should be used only if the preceding sentence expresses a  complete idea without the quote as colons introduce pauses and this would break the sentence if the sentence before the colon is not complete. Thus, you can introduce a quotation with a colon if the words before the quotation are a complete sentence.

he correct answer is choice c. promoters of ufc events were eager to work with state athletic commissions, without public pressure being a necessary inducement.