$\mathrm{Fe}_{3} \mathrm{O}_{4}$ and $\mathrm{Co}_{3} \mathrm{O}_{4}$ are metal oxides having spinel structure. Considering their CFSEs, the correct statement regarding their structure is
(a)both have normal spinel structure
(b)both have inverse spinel structure
(c)$\mathrm{Fe}_{3} \mathrm{O}_{4}$ has normal and $\mathrm{Co}_{3} \mathrm{O}_{4}$ has inverse spinel structure
(d)$\mathrm{Fe}_{3} \mathrm{O}_{4}$ has inverse and $\mathrm{Co}_{3} \mathrm{O}_{4}$ has normal spinel structure