This is False. Rewareded ads are a great fit for gaming apps, as they can seamlessly merge rewards into the game experience.
Banner ads format gives advertisers a clean and well-understood format to display not only text and images but also rich media and video content. Owing to their simplicity, banner ads generally work for any type of application.
This question is from the Check your Knowledge section of the “Serve the right ad for the right moment” lesson from the “Manage Ad Formats and Inventory with AdMob” unit which is a part of the Get Started with Google AdMob course.