Sodium is put into water to make solution Y. The pH of solution Y is then measured. When powdered substance X is added to solution Y, the pH decreases. Which two compounds could each be substance X?
- A$\text{MgCl}_2$ and $\text{Al(OH)}_3$
- B$\text{MgCl}_2$ and $\text{K}_2\text{O}$
- C$\text{NaCl}$ and $\text{Al(OH)}_3$
- D$\text{NaCl}$ and $\text{K}_2\text{O}$