Question Blocks are blocks in the Super Mario series that Mario can bump to receive his items. Coins, Mushrooms, and many other items can be found in Question Blocks. After a Question Block is bumped, it results in a Used Block or a block which can't be destroyed. ( But they can be destroyed by Mega Mario ) It is arguably Nintendo's most iconic item.
Question Blocks appear throughout the game, Super Mario Bros. 2010 like they do in any New Super Mario Bros. game. They are very common in the game.
Sloppy Question Blocks appear in Super Sloppy Bros., containing Super Mushrooms, Fire Flowers, Stars, 1-Up Mushrooms, Mini Mushrooms, Ice Flowers, Yoshi Eggs, and Coins.