Kirk here. The “quiz” in the article is “くまモン検定” (Kumamon kentei, shown on the screen in back of Kumamon and in the Japanese article to which the English links). Japan has lots of kentei (certification) tests, one of which is Eiken (English kentei). If you’d like to take the test, the link is here:
https://mainichi.jp/english/articles/20221028/p2a/00m/0na/016000c
