Which main component of rhetoric addresses a speaker’s credibility?
a. pathos
b. nithos
c. ethos
d. logos

The correct answer is option c "ethos". Among the rhetorical appeals used in speeches and literature to persuade an audience, ethos is the one that address to a speaker’s credibility. In this mode of persuasion the speaker use the authority or credibility of an expert or celebrity to positive influence in the audience.

the answer is:

b) to show the progression of inventions that took place in the bicycling industry.

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