Sulfur dioxide, $\text{SO}_2$, is introduced into wines so that ethanol is not oxidised by air. To find the quantity of $\text{SO}_2$, a wine sample is titrated using iodine, $\text{I}_2$. In this reaction, one mole of $\text{SO}_2$ is oxidised by one mole of $\text{I}_2$. What change in oxidation number does sulfur undergo in this reaction?
- A$+2$ to $+4$
- B$+2$ to $+6$
- C$+4$ to $+5$
- D$+4$ to $+6$