None.
No college can claim to have a 100% placement guarantee. A college provides you an opportunity to get placed. Whether a person encases that opportunity or they don't make the cut is their individual concern.
However, there are many good B-Schools like IIMs, FMS Delhi, ISB, SIBM, IBS Hyderabad, XIM/XLRI and LPU which might increase your chances to get placed.
Don't fall in the trap or gimmicks of the many institutes that claim to provide 100% placements. It's a modern sham.