Answer:
Option B
Explanation:
As we move down the group, size of metal increases. Be has lower size while $SO_{4}^{2-}$ has bigger size, that's why
$BeSO_{4}$ breaks easily and lattice energy becomes smaller but due to lower size of Be, water molecules are gathered around and hence hydration energy increases.
On the other hand, rest metals i.e, Ca, Ba, Sr have bigger size and that's why lattice energy is greater than hydration energy.
Time-saving Technique.
In the question of finding hydration energy only check the size of atom. Smaller sized atom has more hydration energy.
Thus, in this question, Be is placed uppermost in the group has lesser size and not comparable with the size of sulphates. Hence , $BeSO_{4} is right response.
