The correct option is C Neon
∙ Each shell can accomodate 2n2 electrons. Thus, a fully filled first shell has 2 electrons, second shell has 8 electrons and so on.
∙ Electronic configuration of the elements is given below-
AtomAtomic no.Electronic configurationHydrogen 11Sodium112,8,1Neon102,8Carbon62,4
Only neon has fully filled outermost shell.