A block is released from the top of a smooth inclined plane of inclination `theta` as shown in figure. Let `upsilon` be the speed of the particle after travelling a distance s down the plane. Then which of the following will remain constant ?
A. `v^(2)+2gs sintheta`
B. `v^(2)-2gs sintheta`
C. `v- sqrt(2gs) sintheta`
D. `v+ sqrt(2gs) sintheta`