This column of the periodic table represents the halogen family. This is a family of reactive elements. Compare and contrast how the elements are similar and different. A)The mass numbers differ; they have the same number of protons and valence electrons. B)They have different atomic numbers and mass numbers; they have the same number of electrons. C)They have different atomic numbers and mass numbers; they have the same number of valence electrons. D)They have different numbers of protons, neutrons, and valence electrons; they are all gases at room temperature.