The correct option is A i,iii
(i) and (iii): Diborane undergoes cleavage reactions with Lewis bases (L) to give borane adducts, BH3.L
B2H6+2NMe3→2BH3⋅NMe3
B2H6+2CO→2BH3⋅CO
(ii) diborane gets hydrolysed readily to give boric acid.
B2H6Borane+6H2O→2H3BO3Orthoboric acid+6H2↑Dihydrogen
(iv) Diammoniate salt complex is formed
B2H6+NH3(excess)low temperature−−−−−−−−−→B2H6.2NH3 or [H2B(NH3)2]+[BH4]−
Hence correct option is b.