The Correct answer is “The attacks on American shipping vessels that lead to a buildup of an American naval force”.
Indeed, the reason why French privateers were attacking American shipping vessels was that a treaty of friendship and cooperation was passed with Great Britain during the French Revolutionary Wars, when French Republicans were fighting the very monarchic Great Britain. American politicians were deeply and bitterly divided between supporting the French - who had made it possible for them to win the Revolutionary War and achieve independence from Great Britain - and supporting the British, who sought to destroy the incipient French Republic.
When the Jay Treaty was signed, many Americans as well as the French saw this as pure and simple betrayal of an ally who was instrumental in achieving American independence. Therefore, France authorized French privateers to harass and capture any American vessels they encountered. America did not have a strong, large navy capable of facing the French navy. Therefore, they immediately undertook efforts for the expansion of American naval forces.