A co-ordination complex of cobalt has molecular formula containing five ammonia molecules, one nitro group and two chlorine atoms for one cobalt atom. One mole of this compound produces three mole ions in an aqueous solution. In reacting this solution with excess of silver nitrate solution, two moles of $\mathrm{A}\mathrm{g}\mathrm{C}\mathrm{l}$ get precipitated. The ionic formula of this complex would be –

• A

  $\left[\left(\mathrm{C}\mathrm{o}{\left(\mathrm{N}{\mathrm{H}}_3\right)}_4.\mathrm{N}{\mathrm{O}}_2\mathrm{C}\mathrm{l}\right].\right[\left(\mathrm{N}{\mathrm{H}}_3\right)\mathrm{C}\mathrm{l}]$
• B

  $\left[\left(\mathrm{C}\mathrm{o}{\left(\mathrm{N}{\mathrm{H}}_3\right)}_5\mathrm{C}\mathrm{l}\right].\right[\mathrm{C}\mathrm{l}\left(\mathrm{N}{\mathrm{O}}_2\right)]$
• Correct answer
  C

  $[\left(\mathrm{C}\mathrm{o}{\left(\mathrm{N}{\mathrm{H}}_3\right)}_5\left(\mathrm{N}{\mathrm{O}}_2\right)\right]\mathrm{C}{\mathrm{l}}_2$
• D

  $\left[\left(\mathrm{C}\mathrm{o}{\left(\mathrm{N}{\mathrm{H}}_3\right)}_5\right].\right[{\left(\mathrm{N}{\mathrm{O}}_2\right)}_2\mathrm{C}{\mathrm{l}}_2]\mathrm{}$

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