Answer: the correct answer is Rethoric.
Explanation: Rethoric is the name that receives the study of using persuasion while writing and speaking. By persuading, a person intents to convince other person of something. To such effects, the person uses different techniques, rethorical devices. There are many rethorical devices. An example of a rethorical device may be the use of antithesis that connect and contrast two ideas, negating someone's thesis.