Final answer:
John Adams was tasked with persuading France to ally with the American colonists during the Revolutionary War; French support was crucial for the American victory.
Step-by-step explanation:
John Adams was asked to convince the country of France to form an alliance with the American colonists during the Revolutionary War. Given the historical context, France had an interest in weakening British power and expanding its influence, hence the aim to create a partnership with the rebellious British colonies in America. Adams's diplomacy played a crucial role in securing French support, which was vital to the eventual success of the American Revolution.