CORRECT answer is Ne or Neon.The element which has two SHELLS both of which are completely FILLED with electrons is Neon with electronic configuration (2,8).Helium (He) only has 2 electrons and therefore it has a configuration of 1s2.Argon (AR) electron configuration will be 1s22s22p63s23p6.Electron configuration of Krypton (Kr) : 1s22s22p63s23p63d104s24p6.