The oxidation states of nitrogen in $\mathrm{NO}, {\mathrm{NO}}_2, {\mathrm{N}}_2\mathrm{O}$ and ${\mathrm{NO}}_3^{-}$ are in the order of :

• Correct answer
  A

  ${\mathrm{NO}}_3^{-}>{\mathrm{NO}}_2>\mathrm{NO}>{\mathrm{N}}_2\mathrm{O}$
• B

  ${\mathrm{NO}}_2>{\mathrm{NO}}_3^{-}>\mathrm{NO}>{\mathrm{N}}_2\mathrm{O}$
• C

  ${\mathrm{N}}_2\mathrm{O}>{\mathrm{NO}}_2>\mathrm{NO}>{\mathrm{NO}}_3^{-}$
• D

  $\mathrm{NO}>{\mathrm{NO}}_2>{\mathrm{N}}_2\mathrm{O}>{\mathrm{NO}}_3^{-}$

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