(A) ** United Nations
(B) War Production Board
(C) Double V Campaign
(D) Manhattan Project
EXPLANATIONS BELOW
Concept note-1: -The United Nations 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.
Concept note-2: -Four months after the San Francisco Conference ended, the United Nations officially began, on 24 October 1945, when it came into existence after its Charter had been ratified by China, France, the Soviet Union, the United Kingdom, the United States and by a majority of other signatories.
Concept note-3: -The UN Charter is the constitutive instrument of the United Nations, signed on 26 June 1945. It sets out the rights and obligations of Member States and establishes the principal organs and procedures of the United Nations.
Concept note-4: -The United Nations was established after World War II in an attempt to maintain international peace and security and to achieve cooperation among nations on economic, social, and humanitarian problems.