Which of pairs doesn't exist according to MOT?

(i) H22+⇒B.O=0He2⇒B.0=2−22=0(ii) H2−⇒B.O=2−12=0.5He22+⇒B.O=0(iii) H2+=B.0=1−02=0.5He22−=B⋅O=4−22=1.0(iv) H2−⇒B.O=2−12=0.5He22−⇒B⋅O=4−22=1.0As both H22+ and He2 have zero bond order and hence do not exist