Among the following, the one which is not a "green house gas", is

• A

  $\mathrm{N}_{2} \mathrm{O}$
• B

  $\mathrm{CO}_{2}$
• C

  $\mathrm{CH}_{4}$
• Correct answer
  D

  $\mathrm{O}_{2}$

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