Which of the following is an advantage of having a common currency in the European Union

It allows for easier trading and investing

It allows each government to make its own currancy policies

It makes the countries who join the European Union suffer more economic and hardships

The advantage of having a common currency in the European Union is that it allows for easier trading and investing. This is because businesses and individuals can conduct transactions without having to worry about exchange rates and currency conversion costs. Additionally, a common currency can increase price transparency and market competition, leading to more efficient markets.