Which are formed when an electric discharge is passed through helium, out of the following :
`He^(2+), He^(+), He^(2)^(+), He_(2)`

Options

A. `He^(+), He_(2)`
B. `He_(2), He^(2+)`
C. `He^(2+), He^(+), He^(2+)`
D. None.

Answer

C

Explanation

`He_(2)` is not formed.