The order of screening effect of electrons of $\mathrm{s},\mathrm{p},\mathrm{d}$ and $\mathrm{f}$ orbitals of a given shell of an atom on its outer shell electrons is :

From the given set of species, point out the species from each set having highest ${\mathrm{Z}}_{\mathrm{eff}}$.

(a) ${\mathrm{O}}^{2-}, {\mathrm{F}}^{-}, {\mathrm{Na}}^{+}$

(b) $\mathrm{Li}, \mathrm{Be}, \mathrm{C}$

(c) $\mathrm{He}, {\mathrm{Li}}^{+}, {\mathrm{H}}^{-}$