Which from following gases causes the depletion of ozone layer in upper atmosphere?

The ozone layer in the upper atmosphere is depleted by substances like chlorofluorocarbons and nitrogen oxides. Nitric oxide (NO) is a significant ozone-depleting agent that reacts with ozone ($\mathrm{O}_3$) in a catalytic cycle: $\mathrm{NO} + \mathrm{O}_3 \rightarrow \mathrm{NO}_2 + \mathrm{O}_2$ and $\mathrm{NO}_2 + \mathrm{O} \rightarrow \mathrm{NO} + \mathrm{O}_2$.

$\mathrm{O}_3 + \mathrm{O} \rightarrow 2\mathrm{O}_2$

NO acts as a catalyst, regenerating after each cycle to destroy multiple ozone molecules. Although other nitrogen oxides can contribute, NO is the most direct and potent among the options. The correct choice is $\boxed{\text{A}}$.