Final answer:
The advertising appeal often used for fast-food restaurants and microwave foods is convenience.
Step-by-step explanation:
The advertising appeal that is often used for fast-food restaurants and microwave foods is convenience. Fast-food restaurants and microwave foods are known for providing quick and easy meals that can be consumed on-the-go or prepared with minimal effort. This convenience factor appeals to busy individuals who are looking for a quick and hassle-free meal option.