Carbon monoxide, $\text{CO}$, nitrogen dioxide, $\text{NO}_2$, and sulfur dioxide, $\text{SO}_2$, are all atmospheric pollutants. Which reaction involving these compounds takes place in the atmosphere?
- A$\text{CO}$ is spontaneously oxidised to $\text{CO}_2$.
- B$\text{NO}_2$ is reduced to $\text{NO}$ by $\text{CO}$.
- C$\text{NO}_2$ is reduced to $\text{NO}$ by $\text{SO}_2$.
- D$\text{SO}_2$ is oxidised to $\text{SO}_3$ by $\text{CO}_2$.