The correct answer is C. New York.
The United Nations (UN) is an international organization founded in 1945 after the Second World War by 51 countries committed to maintaining international peace and security, developing friendly relations among nations and promoting social progress, better living standards and human rights. Due to its unique international character, and the powers vested in its founding Charter, the Organization can take action on the issues confronting humanity in the 21st century, such as peace and security, climate change, sustainable development, human rights, disarmament, terrorism, humanitarian and health emergencies, gender equality, governance, food production, and more.
The UN Headquarters is located in New York City, USA. The building was designed by an international team of architects led by Wallace K. Harrison and was dedicated on October 24, 1952. The headquarters complex covers 18 acres (7.3 ha) and is bounded by First Avenue, East 42nd Street, Second Avenue, and East 48th Street. The main building is 39 stories tall and is the tallest building in Manhattan south of Central Park.
The UN Headquarters is a major tourist destination and is open to the public for tours. The complex includes a visitor’s center, a museum, and a theater. The UN Headquarters is also home to the General Assembly, the Security Council, the Economic and Social Council, and other UN agencies.