$\mathrm{KK\sigma }2{\mathrm{s}}^2,\mathrm{\sigma }\ast 2{\mathrm{s}}^2,\{\begin{array}{ll}\mathrm{\pi }2{\mathrm{p}}_{\mathrm{y}}^{2\cdot }& \mathrm{\sigma }2{\mathrm{p}}_{\mathrm{x}}^2\\ \mathrm{\pi }2{\mathrm{p}}_{\mathrm{z}}^2& \end{array}$

above electronic distribution is observed in: 

• A

  atomic nitrogen

• B

  molecular nitrogen

• C

  ${\mathrm{O}}_2^{2-}\text{ion}$

• D

  ${\mathrm{C}}_2^{2-}\text{ion}$