B$.$ Equivalent force systems

Question $2$: The magnitude of force $F$ at distance $x$ as shown below that will cause vertical and rotational equilibrium for the system is most nearly:

A$.F=121kN,x=3\mathrm{.}9m$

B$.F=121kN,x=4\mathrm{.}2m$

C$.F=154kN,x=3\mathrm{.}9m$

D$.F=154kN,x=4\mathrm{.}2m$