A bullet of mass m moving with velocity `upsilon_(1)` strikes a suspended wooden block of mass M as shown in the figure and sticks to it. If the block rises to a height y. the initial of the bullet is
A. `sqrt(2gh)`
B. `(M+m)/(m)sqrt(2gh)`
C. `(m)/(M+m)2gh`
D. `(M+m)/(M)sqrt(2gh)`
