A block of mass 5 kg is placed on a rough inclined plane making an angle of $30 ^ { \circ }$ with the horizontal. The coefficient of friction between the block and the plane is $\sqrt { 3 }$. Find the minimum force applied down the incline required to just start moving the block. (Take $\mathrm { g } = 10 \mathrm {~m} \mathrm {~s} ^ { - 2 } $)
(A) 0 N
(B) 25 N
(C) 50 N
(D) 75 N