Two blocks of masses m = 5 kg and M = 10 kg are connected by a string passing over a pulley B as shown. Another string connects the centre of pulley B to the floor and passes over another pulley A as shown. An upward force F is applied at the centre of pulley A. Both the pulleys are massless. The accelerations of blocks m and M, if F is 300 N are (Take, g = 10 $m{s}^{-2}$) 

• A

  5 $m{s}^{-2}$, zero

• B

  zero 5 $m{s}^{-2}$

• C

  zero, zero

• D

  5 $m{s}^{-2}$, 5$m{s}^{-2}$