Alkali metals, alkaline earth metals, and aluminum all form ions with positive charges equal to

the atomic number.

the group number.

a polyatomic ion.

an ionic bond.

Group # IM going to go w B

In the periodic table, the group number or elements belonging to the same column are elements with the same charge relating to the number of valence electrons which can react with other atoms in their outside shells. In this case, the positive charges pertain to B. group number.