Let's compute the moment of inertia of the object for all three cases.
For (a), masses 1 and 2 are zero distance from the axis of rotation, but masses 3 and 4 are both at a distance of 1m, so the moment of inertia is
Therefore the kinetic energy is
For (b) we notice that it's really the same situation as (a) but with a relabling of the axis. So we get the same answer.
(c) has all the masses at a distane 1m from the axis of rotation so we get
Therefore the kinetic energy is
