Concept:The body responsible for amending the United Nations Charter is the General Assembly.Explanation:Amendment of the U.N.O. Charter is carried out through a formal process involving the General Assembly.A proposed amendment must be adopted by a two-thirds vote of the members of the General Assembly.It then comes into force when ratified by two-thirds of the member states, including all five permanent members of the Security Council.The Charter does not give this amendment duty to the Security Council, the Secretariat, or the Trusteeship Council.Answer:C. General Assembly