A horizontal bridge is built across a river. A student standing on the bridge throws a small ball vertically upwards with a velocity $4{\text{m s}}^{-1}$. The ball strikes the water surface after $4\text{s}$. The height of the bridge above the water surface is ($g=10{\text{m s}}^{-2}$):

1. A
   $56\text{m}$
2. B
   $60\text{m}$
3. C
   $64\text{m}$
4. D
   $68\text{m}$