In which pair, the stronger bond is found in the first species ?
a) ${\mathrm{O}}_2^{-},{\mathrm{O}}_2$
b) ${\mathrm{N}}_2,{ \mathrm{N}}_2^{+}$
c) ${\mathrm{NO}}^{+},{\mathrm{NO}}^{-}$

In pairs II and III only is the stronger bond found in the first species.
I : ${\mathrm{O}}_2^{2-},{\mathrm{O}}_2;$ 

II : ${\mathrm{N}}_2,{ \mathrm{N}}_2^{+};$

III : ${\mathrm{NO}}^{+},{\mathrm{NO}}^{-}$
The bond orders of ${\mathrm{O}}_2^{2-},{\mathrm{O}}_2,{\mathrm{N}}_2,{ \mathrm{N}}_2^{+},{\mathrm{NO}}^{+},{\mathrm{NO}}^{-}$are 1,2,3,2.5,3 and 2 respectively.
Higher is the bond order, stronger is the bond formed.

Hence, the correct option is  (B) .