Question

located in the last column of the periodic table, noble gases are the least chemically reactive elements because they have

answer options:
select one of four
stable proton shells.\tunstable proton shells.
stable outermost electron shells.\tunstable outermost electron shells.

Explanation:

Noble gases are least reactive because their outermost electron shells are full (stable), so they don't readily gain/lose electrons. Proton shells aren't related to reactivity; unstable shells would make elements reactive. So the correct option is the one about stable outermost electron shells.

Answer:

stable outermost electron shells.