the goal of the european union is?

global security
national security
military security
political and economic cooperation

This question I do not know

Well, it's not global since it includes only the countries in Europe.

If it's national, which nation? ("national" implies each nation separately, but how would this happen in a union?)

Now ... you tell me what you think about the other two.

political and economic cooperation

The goal of the European Union (EU) is political and economic cooperation. The EU was created with the aim of promoting peace, stability, and prosperity among its member states by fostering collaboration in various areas such as trade, transportation, environmental standards, and human rights. It is not primarily focused on global security, national security, or military security, although those aspects can be indirectly influenced by EU policies. To confirm this information or gather more details about the EU's goals, you can refer to official EU websites, documents, or reputable sources that provide information about the EU's founding principles and objectives.