Screening effect is not observed in :

Options

A. `He^(+)`
B. `Li^(2+)`
C. `Be^(3+)`
D. In all cases

Answer

D

Explanation

`He^(+),1s^(1), Li^(2+), 1s^(1), Be^(3+), 1s^(1)`. All these ions have only one electron. So they do not have any inner orbital and thus do not experience any screening effect.