Which of the Following Is the Correct Electron Configuration for Copper

Multiple Choice

Which of the following is the correct electron configuration for copper?

A) $1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 4 s^{2} 3 d^{9}$
B) $1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 3 d^{9} 4 p^{1}$
C) $1 s^{2} 2 s^{2} 2 p^{6} 2 d^{10} 3 s^{1} 3 d^{9}$
D) $1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 4 s^{1} 3 d^{10}$
E) $1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 3 d^{10}$