X + O3 → XO + O2 XO + O3 → X + 2 O2 2 O3 → 3 O2 The proposed mechanism can be written in a more gene — Kinetics Chemistry Question

X + O₃ → XO + O₂
XO + O₃ → X + 2 O₂
2 O₃ → 3 O₂

The proposed mechanism can be written in a more general form, as shown above. Species other than Cl can also decompose O₃ through the same mechanism. Which of the following chemical species is most likely to decompose O₃ in the upper atmosphere through the above mechanism?