Level 2-5 (Mario vs. Donkey Kong: Tipping Stars)
From the Super Mario Wiki
The Minis start at the bottom left, with a broad arrangement of Red Girder Rivets and two Circus Kongs lying ahead of them. Initially, the top Circus Kong prevents the Minis from going into the Goal Door, as it starts to juggle them once encountered. The Minis should therefore make use of a pair of Hammers located nearby to stun the Circus Kong, gaining passage to the exit.
The M Coin is found on the right side of the course. From the bottom of this area, the Minis should bounce off a series of two High Springs and pass a girder platform from beneath to collect the coin.
Nintendo 3DS version
Wii U version