Which of the following is a notable contribution of Benjamin Franklin?

Benjamin Franklin is notably recognized as a U.S. diplomat, a role in which he made significant contributions to the foundation of the United States. His diplomatic efforts were particularly critical during the American Revolutionary War, where he worked tirelessly to secure French support for the American colonies. Franklin's charm, wit, and political acumen helped him negotiate the Treaty of Paris in 1783, which officially ended the war and recognized American independence. His ability to foster alliances was integral to America's success as a fledgling nation.

While Franklin was involved in various political and civic activities, his role as a diplomat stands out as one of his most impactful contributions, influencing not only immediate outcomes in terms of foreign support but also setting a precedent for how the United States would engage with other nations in the future. The other roles—such as the First Chief Justice of the Supreme Court, the First Secretary of State, or being the Author of the Constitution—are attributed to other prominent figures in American history and do not reflect Franklin's specific contributions.