Answer:
Outer shell is full
Explanation:
The elements represented by the group D are noble gases.
Noble gases have fully filled outer electronic configuration.
He=[tex]1s^2[/tex]
Ne=[tex]1s^22s^2 2p^6[/tex]
Ar=[tex]1s^22s^2 2p^63s^2 3p^6[/tex]
Kr=[tex]1s^22s^2 2p^63s^2 3p^63d^{10} 4s^2 4p^6[/tex]
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