Which of the following molecular species has unpaired electrons

According to MO theory, the electronic configurations of different molecules or ions are given below:

${\mathrm{N}}_2-14-\mathrm{\sigma }1{\mathrm{s}}^2,{\mathrm{\sigma }}^{*}1{\mathrm{s}}^2,\mathrm{\sigma }2{\mathrm{s}}^2,{\mathrm{\sigma }}^{*}2{\mathrm{s}}^2,\mathrm{\pi }2{\mathrm{p}}_{\mathrm{z}}^2,\mathrm{\sigma }2{\mathrm{p}}_{\mathrm{z}}^2$

${\mathrm{F}}_2-18-\mathrm{\sigma }1{\mathrm{s}}^2,{\mathrm{\sigma }}^{*}1{\mathrm{s}}^2,\mathrm{\sigma }2{\mathrm{s}}^2,{\mathrm{\sigma }}^{*}2{\mathrm{s}}^2,\mathrm{\sigma }2{\mathrm{p}}_{\mathrm{x}}^2,\mathrm{\pi }2{\mathrm{p}}_{\mathrm{y}}^2=\mathrm{\pi }2{\mathrm{p}}_{\mathrm{z}}^2,{\mathrm{\pi }}^{*}2{\mathrm{p}}_{\mathrm{y}}^2={\mathrm{\pi }}^{*}2{\mathrm{p}}_{\mathrm{z}}^2$

${\mathrm{O}}_2^{-}-17-\mathrm{\sigma }1{\mathrm{s}}^2,{\mathrm{\sigma }}^{*}1{\mathrm{s}}^2,\mathrm{\sigma }2{\mathrm{s}}^2,{\mathrm{\sigma }}^{*}2{\mathrm{s}}^2,\mathrm{\sigma }2{\mathrm{p}}_{\mathrm{x}}^2,\mathrm{\pi }2{\mathrm{p}}_{\mathrm{Z}}^2,=\mathrm{\pi }2{\mathrm{p}}_{\mathrm{z}}^2,{\mathrm{\pi }}^{*}{\mathrm{p}}_{\mathrm{y}}^2={\mathrm{\pi }}^{*}2{\mathrm{p}}_{\mathrm{z}}^1$

${\mathrm{O}}_2^{-2}-18-\mathrm{\sigma }1{\mathrm{s}}^2,{\mathrm{\sigma }}^{*}1{\mathrm{s}}^2,\mathrm{\sigma }2{\mathrm{s}}^2,{\mathrm{\sigma }}^{*}2{\mathrm{s}}^2,\mathrm{\sigma }2{\mathrm{p}}_{\mathrm{x}}^2=\mathrm{\pi }2{\mathrm{p}}_{\mathrm{z}}^2,{\mathrm{\pi }}^{*}2{\mathrm{p}}_{\mathrm{y}}^2=\mathrm{\pi }2{\mathrm{p}}_{\mathrm{z}}^2$

In the above all species, ${\mathrm{O}}_2^{-}$ ion only contains one unpaired electron in its antibonding

molecular orbital. So, the correct answer is option “C”