Question 24 - Subtest II: Science Practice Test for the CSET Multiple Subjects Test

Which of the following atoms has 18 electrons?
Select all that apply.

A. \(\text{Li}^+\)
B. \(\text{A}r\)
C. \(\text{He}\)
D. \(\text{S}^{2-}\)
E. \(\text{Ca}^{2+}\)
F. \(\text{O}^-\)