A mass m rest on a horizontal surface. The coefficient of friction between the mass and the surface is p. If the mass is pulled by a force P 3. shown in the figure, the limiting friction between mass and the surface will be

• A.  \[\mu \,mg\]   
• B.         \[\mu \,\left[ mg-\left( \frac{\sqrt{3}}{2} \right)F \right]\]
• C.  \[\mu \,\left[ mg-\left( \frac{F}{2} \right) \right]\]  
• D.         \[\mu \,\left[ mg+\left( \frac{F}{2} \right) \right]\]