What elements are classified as alkaline earth metals?

Alkaline earth metals are specifically found in group 2A of the periodic table, which includes the elements beryllium, magnesium, calcium, strontium, barium, and radium. These metals are characterized by having two electrons in their outermost electron shell, leading to similar chemical properties such as reacting readily with water and forming alkaline hydroxides.

The classification as alkaline earth metals is distinct from the other groups mentioned. For instance, group 1A contains alkali metals, which have a single electron in their outer shell and exhibit different reactivity and chemical behaviors. Groups 3A and 4A include other types of metals and metalloids that do not share the same properties as the alkaline earth metals. Therefore, option B accurately identifies the correct group containing alkaline earth metals.