In urban air containing hydrocarbons, ozone accumulates to harmful levels in photochemical smog. The best explanation is that

Aperoxy radicals, formed from hydrocarbons, oxidise $NO$ to $NO X_{2}$ without consuming $O X_{3}$
Bhydrocarbons absorb sunlight and directly convert $O X_{2}$ into $O X_{3}$
Chydrocarbons react with $NO X_{2}$ to give back $N X_{2}$ and $O X_{2}$
Dperoxy radicals react with $O X_{3}$ to give $NO$

Answer: A

Hydrocarbons are oxidised to radicals, e.g.

RO X_{2} \cdot + NO RO \cdot + NO X_{2}

. This converts

NO

NO X_{2}

by a path that does not use up ozone, so the

NO X_{2}

can photolyse again so the ozone formed in

O + O X_{2} O X_{3}

is not removed by

NO

and accumulates.