<s>[INST] The concept of an “internal market” in the European Union (EU) refers to an economic situation in which goods, services and people move freely across borders and without regulatory obstacles within the EU. The development of such a market is considered a key element of European integration. Given the importance of this concept, there is an extensive literature on this topic. Despite the fact that the concept has been discussed extensively, there is still confusion about what it encompasses. The following questions highlight some of the challenges that are presented by this concept: 

1. How is the concept of an internal market defined?[/INST]