IMAT 2017 Q42 [Electron Structure]

Which one of the following options gives the correct electron structure of the particle _8^{16}O^{2-}?

A. 1s^22s^22p^63s^23p^4
B. 1s^22s^22p^4
C. 1s^22s^22p^2
D. 1s^22s^22p^63s^23p^6
E. 1s^22s^22p^6