The correct answer is C. The Economic and Social Council (ECOSOC) is one of the six principal organs of the United Nations. It is responsible for promoting international economic and social cooperation and development, and for coordinating the economic and social work of the United Nations and its specialized agencies.
The General Assembly is the main deliberative organ of the United Nations. It is composed of all 193 Member States of the United Nations. The General Assembly meets in regular sessions every year, and in special sessions when necessary.
The Security Council is responsible for maintaining international peace and security. It has 15 members, five of which are permanent members (China, France, Russia, the United Kingdom, and the United States) and 10 of which are elected by the General Assembly for two-year terms.
The Trusteeship Council was established to oversee the administration of trust territories, which were territories that were not self-governing and were placed under the administration of a trusteeship agreement between the United Nations and one or more Member States. The Trusteeship Council completed its work in 1994, when the last trust territory, Palau, became independent.
The International Court of Justice is the principal judicial organ of the United Nations. It settles legal disputes between States and gives advisory opinions on legal questions referred to it by authorized United Nations organs and specialized agencies.