Rank the elements in order according to their ionization energy: Argon, Astatine, Polonium, Chloride
a) Chloride < Argon < Astatine < Polonium
b) Chloride < Astatine < Argon < Polonium
c) Argon < Astatine < Chloride < Polonium
d) Astatine < Chloride < Argon < Polonium