What is the purpose of an argument?

A. to give facts about an informational topic

B. to share an opinion that is supported by evidence

C. to list evidence you want to share with readers

D. to explain ways someone might disagree with you

The purpose of an argument is generally to present and defend a particular viewpoint or opinion, supported by evidence and reasoning, in order to persuade others or engage in a rational discussion. Therefore, the most appropriate answer is B. to share an opinion that is supported by evidence.