Which of the following represents the lattice structure of $F{e}_{0.95}O$?

The correct option is B
$F{e}^{2+}$ can be easily oxidised to $F{e}^{3+}$ readily. To maintain the electrical neutrality when this change occurs, we need to ensure that 2/3rd of the missing $F{e}^{2+}$ is replaced by $F{e}^{3+}$ as
$3F{e}^{2+}=2F{e}^{3+}$
The closed dots represent $F{e}^{2+}$ and in option b, it is clear that three of these are missing, which are being replaced with 2 $F{e}^{3+}$ ions.