Starbursts Kit-Kat Bars Skittles Hershey Kisses 
Answer: Kit-Kat Bars
If you picked Kit-Kat bars based on the fact that you like Kit-Kat bars, then congratulations on your stomach making an excellent guess on your behalf. But no matter how much you think you like Kit-Kat bars, we’ve got news for you: there’s no way you love the little chocolate covered wafers like the Japanese love them.
How much does Japan love Kit-Kats? Not only are Kit-Kat bars the single best selling candy in the entire country, but you can get Kit-Kat bars in a wide variety of flavors (like apple, strawberry, and even green tea) as well as regional variants across the country. All told, there are more than 300 varieties of Kit-Kat bars, which seems like an absurd number (to everyone but the Kit-Kat loving citizens of Japan, apparently).
So why Kit-Kats? The success of the brand in Japan is a fascinating intersection of business practices, culture, and language. First, Nestlé introduced flavor varieties to deal with the practice of heavy stock rotation within Japanese convenience stores—if Kit-Kats only came in one flavor, then they would risk being rotated out in favor of some new candy. By introducing new flavors based on public tastes, seasons, and tailored for regions (and then frequently adding and removing flavors), Nestlé created a situation where they were controlling the rotation internally and keeping the product fresh and interesting to consumers.
Second, there’s a tradition in Japan known as “omiyage,” very similar to the practice in many other cultures of bringing back souvenirs for friends and family after traveling. Unlike the trinkets often brought back in other cultures, however, like a little statue of a landmark or a key chain, omiyage gifts are typically food. By creating so many regional varieties of their candy, Nestlé was able to tap into the tradition of omiyage, because no matter where you go in Japan, you can find unique varieties of Kit-Kat bars.
Finally, the name “Kit-Kat” sounds like, but is not actually derived from, the Japanese phrase “Kitto Katsu”, a phrase frequently used to wish good luck to someone that translates to “you will surely win”. As a result, giving a Kit-Kat to someone is like giving them a good luck charm—it’s a very popular token to give, especially to students ahead of exams.