Match the items in Column-$I$ with the compounds in Column-$II$.

Column-$I$	Column-$II$
$(A)$ Acid rain	$(1)$ $CHCl_2-CHF_2$
$(B)$ Photochemical smog	$(2)$ $CO$
$(C)$ Combination with hemoglobin	$(3)$ $CO_2$
$(D)$ Depletion of ozone layer	$(4)$ $SO_2$
	$(5)$ Unsaturated hydrocarbons

(A-4, B-5, C-2, D-1) The correct matches are: $(A-4), (B-5), (C-2), (D-1)$.
$(A)$ Acid rain is primarily caused by $SO_2$ and $NO_x$ emissions.
$(B)$ Photochemical smog is formed by the reaction of unsaturated hydrocarbons and nitrogen oxides in the presence of sunlight.
$(C)$ Carbon monoxide $(CO)$ binds strongly with hemoglobin,reducing its oxygen-carrying capacity.
$(D)$ Ozone layer depletion is caused by chlorofluorocarbons (CFCs) like $CHCl_2-CHF_2$.