Speakers should adapt their attire to the speaking situation

The word "restaurant" makes people think of a building where you go to eat. Like all words, "restaurant" is an example of a _____

a. symbol b. transition c. metaphor d. syntax

Which of the following best describes the concept of "source credibility"? 

A. Features of the speaker like attractiveness, intelligence, and energy B. Audience perceptions of presenter effectiveness C. The presenter's education and experience on the topic D. The audience's ability to see, hear, and analyze the presentation