V and W are two compounds. Each contains a different Group 2 element. A separate sample of each solid is placed in water, the mixture is shaken, and the pH of the solution formed is measured. The pH readings are: V = $13.6$, W = $9.4$. Which row could be used to identify V and W?
- AV: $\text{BaSO}_4$; W: $\text{MgSO}_4$
- BV: $\text{MgSO}_4$; W: $\text{BaSO}_4$
- CV: $\text{Ba(OH)}_2$; W: $\text{Mg(OH)}_2$
- DV: $\text{Mg(OH)}_2$; W: $\text{Ba(OH)}_2$