In sodium chloride, ${\mathrm{Cl}}^{-}$ions form $\mathrm{CCP}$arrangement. In which sites, ${\mathrm{Na}}^{+}$ions will occupy in this structure

The ${\mathrm{Cl}}^{-}$ ions form a CCP configuration in sodium chloride. In this structure, octahedral voids will house ${\mathrm{Na}}^{+}$ ions. Its coordination number will be 6. The radius ratio provides proof of this. The radius ratio for octahedral voids is $\frac{\mathrm{r}}{\mathrm{R}}=0.414$. The ratio of the radius ($r$) of the atom or ion that can perfectly fit in the octahedral vacuum created by spheres of radius ($R$) is known as the radius ratio. $\frac{\mathrm{r}}{\mathrm{R}}=\frac{95}{181}=0.524$.

Hence the correct answer is C) All octahedral voids.