Assertion: The total kinetic energy of a rolling solid sphere is the sum of translational and rotational
kinetic energies.
Reason: For all solid bodies, total kinetic energy is always twice of translational kinetic energy. [AIIMS 2017] 

The kinetic energy of a rolling solid sphere  

$=K_{\text{trans }}+K_{\text{rot }}=\frac{1}{2}m{v}^2+\frac{1}{2}I{\omega }^2$

$=\frac{1}{2}m{v}^2+\frac{1}{2}\times \frac{2}{5}m{R}^2{\omega }^2$

$=\frac{1}{2}m{v}^2+\frac{1}{5}m{v}^2$     $\left(\because \omega =\frac{v}{R}\right)$

$=7/10m{v}^2$

Hence, total kinetic energy is sum of translation and rotational kinetic energies.

For different solid bodies, total kinetic energy is not always twice of translation kinetic energy. Hence,  Assertion is correct but Reason is incorrect.