The correct answer to this open question is the following.
Although there are no options attached we can say the following.
What has been the greatest advantage of creating groups like the EEC, EU, and NAFTA?
The greatest advantage of creating groups like the EEC, EU, and NAFTA is that countries can form trade regions or trade "blocks" that benefit their economic interests. These trade agreements allow their members to freely trade with no or minimum tax barriers, benefiting their exportations and importations rate.
Let's put the example of NAFTA.
On December 17, 1992, Presidents of Mexico, the United States, and Canada signed NAFTA. They were Carlos Salinas, George H. W. Bush, and Brian Mulroney. This would be the largest free trade area in the world. The entering President, Bill Clinton, supported NAFTA principles but wanted the addition of some clauses on environment protection and better labor agreements. According to President Clinton, a result of the North America Free Agreement (NAFTA) would be increased jobs and lower prices.
NAFTA has been recently renegotiated by the three countries and the new agreement is called USMCA, United States, Mexico, and Canada Agreement.
