Which of the following gases causes depletion in ozone layer?

The ozone layer in the stratosphere protects Earth from harmful ultraviolet radiation. Depletion occurs primarily through catalytic reactions with certain chemical species.

Helium is inert and non-reactive with ozone. Carbon dioxide contributes to global warming but does not deplete ozone. Hydrogen gas shows no known ozone-depleting properties.

Nitric oxide participates in a catalytic cycle:
$NO + O_3 \rightarrow NO_2 + O_2$
$NO_2 + O \rightarrow NO + O_2$

The net reaction is $O_3 + O \rightarrow 2O_2$, with nitric oxide acting as a catalyst to destroy ozone molecules.

Nitric oxide is therefore the ozone-depleting species.