A $0\mathrm{.}25-$in$-$thick plate is loaded in three$-$point bending. The load $F$ fluctuates from $0$ to $350$ lb $.$ After some time, it is noticed that a crack has formed on the tensile side, as shown. When $F$ is at its maximum during the cycle, which of the following options is closest to the factor of safety against sudden fracture $(n=\frac{K_l}{K_l})?$ The material has a fracture toughness of $22ks{i}^{in}{?}^{\frac{1}{2}}.$ Assume $$ is $0\mathrm{.}97.$

A$.3\mathrm{.}2$

B$.2\mathrm{.}0$

C$.1\mathrm{.}4$

D$.4\mathrm{.}5$