Final answer:
Aristotle was the first to define the term 'rhetoric' as the art of persuasion.
Step-by-step explanation:
The correct answer is C. Aristotle. Aristotle, an ancient Greek philosopher, was the first to give a systematic definition of rhetoric. In his work 'Rhetoric', he defined rhetoric as the art of persuasion and explained its three main forms: ethos, pathos, and logos.
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