Final answer:
The statement is false; not all European Union countries use the euro. Countries like Great Britain, Denmark, and Sweden retain their own currencies, despite many EU nations having adopted the euro.
Step-by-step explanation:
The statement that the euro has replaced the currencies of all of the countries of the European Union is false. While the euro has been adopted by many EU member states as part of their efforts to integrate their economies, it is not true that all EU countries use the euro as their main currency. Major economic players like Great Britain have kept their traditional currencies, such as the pound sterling, and other countries like Denmark and Sweden also continue to use their own currencies. The euro certainly plays a central role in the European economy, as it has been adopted by a number of EU countries, including some very large economies such as France, Germany, and Italy. However, there are nations that have opted to keep their national currencies, illustrating the complexity and diversity of currency use within the EU.
It is important to note that the decisions on monetary policies for countries using the euro are made by the European Central Bank, which has members from all euro nations. This means that countries using the euro have limited control over their own monetary policy.