Which appeal is most clearly an example of ethos?
o
a. support the bill if you like coughing and looking at smokestacks.
o
b. as a dietician, i must stress that we should eat fewer
carbohydrates.
o
c. raising the driving age to 18 is the best way to keep the streets
safe.
o
d. a recent poll shows that far more students favor uniforms than
don't.

B. As a dietician, I must stress that we should eat fewer carbohydrates.

Explanation:

 The appeal of Logos is the word or message itself; of Pathos is the emotion, and Ethos is a way of persuasion that involves the character of the speaker, his or her reputation and "ethics' , all this as a way of convincing the audience.  An advice concerning what kind of food we should we eat is much more reliable if it comes from a dietician.

I believe the answer is D.