The correct option is (4) Be(OH)2.
Explanation:
Basic nature of hydroxides of alkaline metals -
Except Be(OH)2 all hydroxides are basic in nature. this character increases down the group
- wherein
Due to weak M-OH bond which break easily heterolytically to yield OH-
As we know that Be(OH)2 is emphoteric in nature ehile rest all alkaline earth metal hydroxide are basic in nature.