As seen from the attached concept, KEtot is same for all the bodies.
MI of ring and hollow cylinder are same for a given mass m and radius R.
Hence, KErot is same for both ring and hollow cylinder.
MI of Isolidcylinder>Ihollowsphere>Isolidsphere
Iring=Ihollowcylinder>Isolidcylinder>Ihollowsphere>Isolidsphere
Hence, Rotational KE of the objects having the greater MI is more compared to others.
τ=Iα
All objects are subjected to same torque. Object having least MI has the maximum angular acceleration.
Hence, solid sphere has the max angular acceleration.
Time taken to reach the bottom is maximum for
Ring or hollow cylinder.