A body of mass m is projected horizontally with a velocity v from the top of a tower of height h and it reaches the ground at a distance x from the foot of the tower. If a second body of mass 2m is projected horizontally from the top of a tower of height 2h, it reaches the ground at a distance 2x from the foot of the tower. The horizontal velocity of the second body is

• A. \[~v\]               
• B.        \[2v\]
• C. \[\sqrt{2v}\]                  
• D.        \[v/2\]