Two stones are thrown from the top of a building with the same speed\[u\], one in the upward direction and the other in the downward direction. When they reach the ground/they acquire certain velocities \[{{v}_{1}}\] and \[{{v}_{2}}\] respectively. What is the ratio of \[{{v}_{1}}\] and\[{{v}_{2}}\]?

• A. \[1:1\]                 
• B.        \[1:2\]
• C. \[2:1\]               
• D.        \[2:3\]