A body of mass M is kept n a rough horizontal surfasce (friction coefficient `=mu`). A person is trying to pull he body by applying a horizontal force but the body is not moving. The force by the surface on A is F, where
A. `F=Mg`
B. `F=muMgf`
C. `Mg le F le Mgsqrt(1+u^(2))`
D. `Mg ge F ge Mgsqrt(1+u^(2))`
