Which of the following option does not represent ground state electronic configuration of an atom?

Options

A. `1s^2,2s^2,2p^6,3s^2,3p^6,3d^84s^2`
B. `1s^2,2s^2,2p^6,3s^2,3p^6,3d^9,4s^2`
C. `1s^2,2s^2,2p^6,3s^2,3p^6,3d^10,4s^1`
D. `1s^2,2s^2,2p^6,3s^2,3p^6,3d^5,4s^1`

Answer

B