What is the correct electronic configuration of the central atom in ${\mathrm{K}}_4\left[\mathrm{F}\mathrm{e}{\left(\mathrm{C}\mathrm{N}\right)}_6\right]$ based on crystal field theroy?

• A

  ${\mathrm{t}}_{2\mathrm{g}}^4{\mathrm{e}}_{\mathrm{g}}^2$
• Correct answer
  B

  ${\mathrm{t}}_{2\mathrm{g}}^6{\mathrm{e}}_{\mathrm{g}}^0$
• C

  ${\mathrm{e}}^3{\mathrm{t}}_2^3$
• D

  $\mathrm{ }{\mathrm{e}}^4{\mathrm{t}}_2^2$

Hence, the correct answer is option: 'B'.