X is either nitrogen or sulfur, and in a car engine it forms the pollutant oxide Y. Y is then further oxidised to Z in the atmosphere. During this additional oxidation, $1\,\text{mol}$ of Y reacts with $0.5\,\text{mol}$ of gaseous oxygen molecules. Which of the following statements about X, Y and Z could be correct?
- A1, 2 and 3 are correct
- B1 and 2 only are correct
- C2 and 3 only are correct
- D1 only is correct