Final answer:
The United Nations Security Council requires 9 votes to pass legally binding resolutions.
Step-by-step explanation:
The institution that requires 9 votes to pass resolutions that are legally binding is the United Nations Security Council (A). Each of the five permanent members of the council—the U.S., Russia, Britain, France, and China—has the power to veto council decisions. However, for non-veto decisions, at least nine of the fifteen council members must agree for a resolution to pass. The European Union Parliament, World Health Organization, and International Monetary Fund operate under different voting requirements for the passage of resolutions.
The United Nations Security Council is composed of 15 members, 5 of which are permanent members (United States, Russia, Britain, France, and China) and have the power to veto council decisions. In order for resolutions passed by the Security Council to be legally binding, they require 9 votes in favor.