The following elements are arranged in order to enhance the metallic properties

The following elements are arranged in order to enhance the metallic properties: 1Na, Mg, Al2. Sr, Ca, K3. Ca, Sr, Rb4. Ba, Sr, Ca

In this matter, one simply cannot do without the Periodic Table of Chemical Elements. So I will immediately note that it is alkali metals that exhibit the most metallic properties. It should also be noted that the larger the atomic radius of a chemical element, the more metallic properties are manifested. So all options except 3 are eliminated. But exactly option 3 is suitable. Rb (rubidium) is an alkaline element with distinct alkaline properties. And strontium has a greater atomic radius than calcium and therefore its metallic properties are more pronounced.