AC (Axiom of Choice)

The Axiom of Choice (AC) is a principle in mathematics stating that given a collection of non-empty sets, it's possible to select exactly one element from each set, even if there's no explicit rule for making these choices. Think of it like having an array of boxes, each containing at least one item; AC assures you can pick one item from each box, even if the boxes are infinite or the selection rule isn't specified. It's fundamental in many areas of math, enabling the proof of results that rely on making countless such choices simultaneously.