\(Ne :[ He ] 2 s ^2\,2 p ^6\)
\(He : 1 s ^2\)
\(Be: 1 s ^2 \,2 s ^2\)
\(N :[ He ] 2 s ^2 \,2 p ^3\)
Although \(Ne, He\) and \(N\) all have fully filled stable configuration but the electron is to be removed from a is shell in case of \(He.\) \(1s\) shell being closest to the nucleus makes quite tough to remove an electron from it. Thus, the element having the highest \(I.P.\) value is Helium.