The correct option is B Be(OH)2
Amphoteric substances are those substances which can react both as acid and as a base.
Be(OH)2 is amphoteric in nature since it can react both with acid and base.
Be(OH)2+2HCl⟶BeCl2+2H2O
Be(OH)2+2NaOH⟶Na2[Be(OH)4]
Mg(OH)2, Ca(OH)2,and Sr(OH)2 are basic hydroxides.
Hence, option (b) is correct.