Immediacy can be communicated verbally or nonverbally

What type of persuasive "question" is addressed in the following thesis statement?

"Violent video games and movies lead to aggressive and violent behavior among teenagers." A) Question of fact B) Question of value C) Question of policy D) Question of taste

What is the term used to describe the sentence that expresses the specific purpose of your speech?

a. central idea b. specific purpose c. general purpose d. subject