$X$ and $Y$ are oxides of two different Period 3 elements. When one mole of $Y$ is mixed with water, the resulting solution is neutralised by exactly one mole of $X$. What might the identities of $X$ and $Y$ be?
- A$X = \text{Al}_2\text{O}_3,\; Y = \text{P}_4\text{O}_{10}$
- B$X = \text{Al}_2\text{O}_3,\; Y = \text{SO}_3$
- C$X = \text{Na}_2\text{O},\; Y = \text{P}_4\text{O}_{10}$
- D$X = \text{Na}_2\text{O},\; Y = \text{SO}_3$