A bullet of mass $$0.25\,kg$$ moving horizontally with velocity $$v$$ strikes a stationary block of mass $$1.00\,kg$$ suspended by a long inextensible string of negligible mass and length. The bullet gets embedded in the block and the system rises up to maximum height $$h=19.6\,cm$$ as shown in the figure. The value of initial speed $$v$$ of the bullet is

A

$$5.9\,m/s$$

B

$$7.8\,m/s$$

C

$$9.8\,m/s$$

D

$$11.8\,m/s$$