A block of mass 5 kg is moving on an inclined plane which makes an angle of 30° with the horizontal. Friction coefficient between the block and inclined plane surface is $$\frac{\sqrt{3}}{2}$$. The force to be applied on the block so that the block will move down without acceleration is _______N
$$(g=10m/s^{2})$$

A

15

B

12.5

C

25

D

7.5