According to the electron configuration, which atom will be the most reactive?
A) 1s^2 2s^2
B) 1s^2 2s^2 2p^6 3s^2
C) 1s^2 2s^2 2p^6 3s^2 3p^6
D) 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2
