The answer you are looking for is option C. A pause or hesitation.
<em>A comma can be used to give direction either to a reader or a speaker to where to take a pause,</em><em></em>and also to make the sentence most effective and convincing. In other words, a comma can be used near the end of a sentence to separate contrasted coordinate elements or to indicate a distinct pause or shift.
The correct answer to this question is the title. To cite an entry in an encyclopedia, use the title instead of the author name as the opening item in the citation. Thank you for posting your question. I hope that this answer helped you. Let me know if you need more help.
