The best example of the bandwagon type of propaganda from the options provided is b. everyone loves Pepsi.
The bandwagon technique aims to persuade people to adopt a certain belief or take a specific action because "everyone else is doing it." This option explicitly communicates that a large group of people enjoys Pepsi, implying that you should too simply because others do.
Option a is more about celebrity endorsement, while c focuses on hydration and a lifestyle claim. Option d emphasizes a target demographic (moms) but does not convey the idea of widespread popularity as directly as option b.