Rocky Road (microgame)
From the Super Mario Wiki
The objective of the game is for the player to break the rocks that are on the road, so a car can travel along it. There are two rocks on the road; one is randomly placed before the curve in the road, and the other is randomly placed after. If the car hits either of the rocks, it will explode and the game will be lost. However, if the rocks are broken by the end of the game, the player will win. There is a sign saying "Caution: Rocks!" on the road.