Answer:target audience
Explanation:
Target audience is an audience you intend to reach with your research or product.
Whatever result you are looking for you aim at finding them from that group of people or from that audience .
You have particular singled them out based on what you want to achieve with your product or research in this case.
The reason he is targeting these students is because his speech is about letting students know the benefits of getting involved in extracurricular activities hence the people who will have to hear about these benefits are those who are not yet participanting in any extracurricular activity .
This the audience that stand to benefit more from his speech .