Correct Answer - B
the shortest wavelength of Brackket series is corresponding to the transition of electron between `n_(1)4` and `n_(2)=oo`.
Similarity , the shortest wavelength of Balmer series is coresponding to the transition of electron between `n_(1)=2` and `n_(2)=oo`.
` (Z)^(2)(13.6/4) or Z=2`