What is the European Union (EU)?

The European Union (EU) is indeed defined as a political and economic union of European countries. This structure encompasses a wide range of policies and regulations that promote economic cooperation, political stability, and social development among its member states. The EU allows for the free movement of goods, services, capital, and people across its internal borders, fostering a single market that enhances trade and investment opportunities among its members. In addition to economic collaboration, the EU also engages in political integration and has established various common policies to address issues such as environmental protection, competition, and regional development.

The other options do not accurately represent the EU's scope or functions. It is not merely a military alliance, as that description fits organizations like NATO. While the EU does facilitate trade agreements, it is more than just a trade agreement; it integrates many aspects of governance and cooperation among its member states. Lastly, while the EU promotes human rights, it is not solely an international organization focused on this area. The comprehensive nature of the EU goes beyond these narrower definitions, making the characterization as a political and economic union the most accurate representation.