The correct electronic configuration for the ground state of silicon (atomic number $= 14$) is

• A
  $1 s^2 2 s^2 2 p^6 3 s^2 3 p^2$
• B
  $1 s^2 2 s^2 2 p^6 3 p^4$
• C
  $1 s^2 2 s^2 2 p^4 3 s^2 3 p^4$
• D
  $1 s^2 2 s^2 2 p^6 3 s^1 3 p^5$