The answer is C: Ethos promotes the credibility or character of the speaker.
Ethos is one of the three modes of persuasion discussed by Aristotle in his book, Rhetoric (the other two are pathos and logos).
Ethos is characterized by an appeal to an exemplary moral fiber in the speaker that, through his or her experience and knowledge, bestows upon his or her arguments an ethical quality that aims at persuading the audience by an appeal to what is culturally valued as good or best.
