In the context of the Stable Marriage Problem, how does the Gale$-$Shapley algorithm determine the stability of a matching?

By ensuring an equal number of men and women in the final matching.

By guaranteeing that no individual prefers an unmatched partner over their current match.

By matching individuals based on a random selection process to avoid bias.

By confirming that there are no blocking pairs where both individuals prefer each other over their current matches.

By ensuring that each individual is matched with their top preference.