Final answer:
The elements As (Arsenic), Sb (Antimony), and Bi (Bismuth) have the same number of valence electrons, each possessing five as they belong to Group 15 of the periodic table.
Step-by-step explanation:
The student has asked which of the following groups of elements have the same number of valence electrons. Elements in the same group (or column) on the periodic table share the same number of valence electrons. This characteristic gives them similar chemical properties. For example, alkali metals like lithium and sodium have one valence electron, and halogens like fluorine and chlorine have seven valence electrons.
Looking at the options provided, we can check the periodic table. Rb (Rubidium), Ga (Gallium), As (Arsenic), and Ar (Argon) are not in the same group, so they do not have the same number of valence electrons. Rb is an alkali metal (Group 1), Ga is in Group 13, As is in Group 15, and Ar is a noble gas (Group 18).
Similarly, Sb (Antimony), Sn (Tin), and Bi (Bismuth) don't share the same number of valence electrons since Sb is in Group 15, Sn is in Group 14, and Bi is in Group 15.
As (Arsenic), Sb (Antimony), and Bi (Bismuth) all have five valence electrons since they belong to Group 15, known as the pnictogens. This group is characterized by elements having five valence electrons.
Lastly, Ar (Argon), Kr (Krypton), and Br (Bromine) also do not possess the same number of valence electrons as Ar and Kr are noble gases with eight valence electrons (Group 18), and Br is a halogen with seven valence electrons (Group 17).
Therefore, the group As, Sb, Bi are the ones that share the same number of valence electrons.