Answer:
c. likability, expertise, familiarity
Explanation:
In order for a speaker to be more turstworthy when delivering a persuasive message he has to be considered by the audience as likeble, someone that the people like and is fond of is easier that he could persuade people, the expertise helps him to have a supported voice from which he can talk to people form a perspective of knowledge on the topic he is talking about, and the familiarity brings him closer to the audience, the audience is already close to him and know him, this puts him one step ahead to convinve and persuade the people.
