Sulphur dioxide is one of the components of polluted air. \( \mathrm{SO_2} \) is also a major contributor to acid rain. The correct and complete reaction to represent acid rain caused by \( \mathrm{SO_2} \) is:
\( 2\mathrm{SO_2} + \mathrm{O_2} \rightarrow 2\mathrm{SO_3} \)
\( \mathrm{SO_2} + \mathrm{O_3} \rightarrow \mathrm{SO_3} + \mathrm{O_2} \)
\( \mathrm{SO_2} + \mathrm{H_2O_2} \rightarrow \mathrm{H_2SO_4} \)
\( 2\mathrm{SO_2} + \mathrm{O_2} + 2\mathrm{H_2O} \rightarrow \mathrm{H_2SO_4} \)
