Answer:
the best example of the strategy "tap into fandoms" is: People who love the Marvel™ comic series attend Comic Con™ every year.
"Tap into fandoms" is a marketing strategy that involves targeting a specific group of fans or enthusiasts and using their passion for a particular brand, product, or activity to promote and sell products or services. In this case, the example of people who love the Marvel™ comic series attending Comic Con™ every year demonstrates how a company can tap into the enthusiasm and loyalty of a particular fan base in order to promote and sell products or services. This is in contrast to the other examples, which do not involve a specific fan base or community of enthusiasts.
Hope you understand!