From Wikipedia:

"Tottoko Hamtaro Nazonazo Q: Kumo no Ue no ?-Jō is a quiz video game released for the Nintendo DS in Japan in 2005. Eschewing an explorable world, this game consists of a large collection of quiz questions, most of which are wordplay-based riddles. A fraction of questions is dedicated to subjects such as mathematics and science, and to trivia about the Ham-Hams. Progress in the game is made by answering multiple levels of randomly selected questions in a multiple-choice format – though all but one kana of each answer is blacked out. To successfully answer these, the player is tasked with first playing a training mode which offers hints and the ability to reveal blacked-out kana, and thus learn the answer to each question in advance. During play, sunflower seeds are earned, which can be used as currency for furnishing a virtual home."

Tottoko Hamtaro Nazo Nazo Q Kumonoue no ? Jou screenshots