A thin hollow sphere of mass $'m'$ is completely filled with a liquid of mass $'m'$. When the Sphere rolls with a velocity $'c'$, kinetic energy of the system is (neglect friction):

Question

$$\begin {array} {1 1} (a)\;\frac{1}{2}\;mv^2 & \quad (b)\;mv^2 \\ (c)\;\frac{4}{3}\;mv^2 & \quad (d)\;\frac{4}{5}\;mv^2 \end {array}$$