In the given figure, the block of mass \( m \) is dropped from the point ‘A’. The expression for kinetic energy of block when it reaches point ‘B’ is:
\( \frac{1}{2} m g y_0^{2} \)
\( \frac{1}{2} m g y^{2} \)
\( mg ( y - y_{0} ) \)
\( mg y_{0} \)