Concept:The approval of the United Nations annual budget is a financial and administrative power of the main UN deliberative body.Explanation:The UN budget is reviewed and approved by the General Assembly.This body includes representatives from all member states.The General Assembly allocates funds and oversees financial and administrative matters.Its decision on the budget determines the resources available for UN programmes and activities.The Secretariat implements the budget, while the Security Council and Trusteeship Council do not handle budget approval.Answer:A. The General Assembly