Benelux multiple choice (Belgium, Netherlands, Luxembourg)

All three countries were founding members of the EU

Brussels in Belgium and Luxembourg in Luxembourg are both EU capitals

The Netherlands borders France on Sint Maarten/Saint Martin in the Caribbean

Luxembourg is a Grand-Duchy

Both Belgium and The Netherlands have a Limburg, there's also a province of Luxembourg in Belgium and a few Brabants in Belgium and The Netherlands. To make life even more confusing, there is a Zeeuws-Vlaanderen (Flanders) in the Netherlands

The European Court of Justice is in Luxembourg

The international Court of Justice is in Den Haag/The Hague, the Netherlands

Most of the Netherlands and approx. 60% of Belgium have Dutch as their first language

Luxembourg is listed over 100.000 USD by any reliable source (IMF, World Bank, CIA), roughly double of either the Netherlands or Belgium

Both countries have French and German as an official language, Dutch is official in the Netherlands and Belgium.

Schiphol - Amsterdam Airport in the Netherlands is one of the largest airports in Europe

Many comments indicate QM does not like Belgium :)

The Netherlands and Belgium both border the North Sea

From the Netherlands, Luxembourg also became independent from the Netherlands (in 1879)

All three countries switched at introduction of the Euro