The specific purpose for scott's persuasive speech is "to persuade my audience to eat locally produced food." according to your textbook, scott is speaking on a question of

The answer to this question is Policy
question of policy  is a persuasive question that aimed to persuade others to change their stance from the current status quo into a desired situation.
This type of question is often used by companies to find out what the customers need and create an appropriate product to target them.