Chemistry

An atom in the ground state has seven valence electrons. Which electron con??guration could represent the valence electron configuration of this atom in the ground state?

(A) 3s13p6
(B) 3s63p1
(C) 3s13p43d2
(D) 3s33p43d1
(E) 3s23p5
Test ID: 1390
Source: SAT Chemistry Practice Test