The correct answer is A. Nothing, the in-text citation is correct.
Step-by-step explanation
A quote is a way of referencing in a text of our authorship what someone else has said. Throughout history hundreds of forms have been developed to quote, however in recent years, these referencing systems have been developed more widely because universities and the scientific world have become more strict with this issue. One of the most accepted and easiest ways to quote is using last name, year, page, in parentheses for references to the author that we want to include in our text. According to the above, the quote from the fragment of the text of the question is correct because it uses the basic parameters mentioned above necessary for a quote (Hauptmann, 2008, p. 137). So, the correct answer is A. Nothing, the quote in the text is correct.