Pulling force making an angle `theta` to the horizontal is applied on a block of weight `W` placed on a horizontal table. If the angle of friction is `alpha`, then the magnitude of force is `alpha` , then the magnitude of force required to move the body is equal to
A. `(Wsinalpha)/(gtan(theta-alpha))`
B. `(Wcosalpha)/(cos(theta-alpha))`
C. `(Wsinalpha)/(cos(theta-alpha))`
D. `(Wtanalpha)/(sin(theta-alpha))`
