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.

Ithink the answer you are looking for is (b).