In a car engine, the non-metallic element X produces the pollutant oxide Y. Y then undergoes further oxidation to Z spontaneously in the atmosphere. In this extra oxidation, $1\,\text{mol}$ of Y reacts with $0.5\,\text{mol}$ of gaseous oxygen. Which statements about X, Y and Z are correct?
- A1, 2 and 3
- B1 and 2 only
- C2 and 3 only
- D1 only