Which of the following diatomic molecules would be stabilised by the removal of an electron?

In ${\mathrm{O}}_2$, molecule, last two electrons are present in anti bonding
orbitals.
${\mathrm{O}}_2\left(8+8=16\right)=\mathrm{\sigma }1 {\mathrm{s}}^2,{\mathrm{\sigma }}^{*}1 {\mathrm{s}}^2,\mathrm{\sigma }2 {\mathrm{s}}^2,{\mathrm{\sigma }}^{*}2 {\mathrm{s}}^2, \mathrm{\sigma }2{{\mathrm{p}}_{\mathrm{z}}}^2,\mathrm{\pi }2{{\mathrm{p}}_{\mathrm{x}}}^2=\mathrm{\pi }2{{\mathrm{p}}_{\mathrm{y}}}^2,{\mathrm{\pi }}^{*}2{{\mathrm{p}}_{\mathrm{x}}}^1={\mathrm{\pi }}^{*}2{{\mathrm{p}}_{\mathrm{y}}}^1$
Removal of one electron from the ${\mathrm{O}}_2$, molecule gives ${\mathrm{O}}_2^{+}$ in which the number of anti bonding electrons is one less and hence, $\mathrm{BO}$ increases. Thus, removal of one electron from ${\mathrm{O}}_2$ stabilises the molecule.