At a pressure of $1$ atmosphere and temperature of $25^{\circ} \mathrm{C}$, $365 \mu \mathrm{~g} \mathrm{~m}{ }^{-3}$ of a pollutant corresponds to mixing ratio of $139$ parts per billion (ppb). The atomic weights: $\mathrm{C}- 12$, $\mathrm{H}-1, \mathrm{O}-16, \mathrm{~N}-14$ and $\mathrm{S}-32$. Which one of the following options most closely represents the pollutant
- $\mathrm{SO}_{2}$
- $\mathrm{NO}_{2}$
- $\mathrm{O}_{3}$
- $\mathrm{CO}$
