Respuesta :

Halogens are the most reactive elements. Halogens include: fluorine, chlorine, bromine, iodine, and astatine
Among all the elements on periodic table, Halogen (17th group) elements are most reactive 'cause of high electronegativity. & among all of them, "Fluorine" is most reactive.

In short, Your Answer would be "Halogens"

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