In which U.S. city was the Charter of the United Nations officially signed in 1945 by representatives of 50 nations, establishing the foundation of the international organization?

💡 Explanation:

The United Nations Conference on International Organization (UNCIO) met in San Francisco from April to June 1945, culminating in the signing of the UN Charter on June 26, 1945. The UN Headquarters were later established in New York City.