Which of the following is not one of the groups on the periodic table?

The story behind the answer

Fluorines is not a periodic table group; fluorine is a single element that belongs to the halogens. The other options—Noble Gases, Alkali Metals, and Halogens—are true groups (vertical columns) whose members share similar properties due to similar valence electron configurations.

Context tip: Alkali metals (Group 1) like lithium and sodium are highly reactive metals; noble gases (Group 18) like neon and argon are very unreactive;