Answer:
B. The EU
Step-by-step explanation:
The E.U (or European Union), created the common Europe currency of Euro, that is shared by most European countries (other than Britain, who still use £.
It's not the UN, for the UN is the meeting of all countries in the world, and is a security force for the world.
It's not the NATO, for the NATO is the North Atlantic Treaty Organization that includes Canada, the United States, and Mexico.
It's not the NAFTA, for NAFTA is also in between Canada, the US, and Mexico, and is a trading system that removed all tariffs in between the countries.