input: Text: What cities in the post-Brexit era could learn from a 14th-century trading bloc As you fly from the country now known as Germany to Britain, the coastal geography of northern European cities gently unfurls. You can see where the sea smacks into them, or where yawning estuaries unfold like funnels between green and brown city and choppy blue water. You can track the snaking rivers and canals that form unrepentant umbilical connections to the settlements set a little further inland. By their nature cities along coasts and rivers developed so they could be open to trade with each other. From the middle of the 13th century, and for some 300 years after, many settlements dotted along this route formed the prosperous Hanseatic League, a European trading confederation of market towns, before the rise of the nation state led to its dissolution. The Hanseatic League is not well known, and today it lives on most prominently in the name of the German national airline Lufthansa, literally the 'Hansa of the skies', whose planes you can look out of – and down towards the Hanseatic cities – on the short journeys between mainland Europe and Britain. The letters HH on the number plates of cars in Hamburg stand for Hansestadt Hamburg: another proud little memory of this hidden history. In the traumatised atmosphere of post-Brexit Britain, it is worth remembering the Hanseatic League. It could point us towards new relationships between progressive city dwellers in a world that otherwise seems to be putting the brakes on modernity. Despite some of Britain's Leave voters longing to inhabit a fantastical realm immune to foreign influence, the reality is patently very different to that. In the late 1300s, Chaucer wrote about characters travelling to Jerusalem, and others who came from Europe; and it was at exactly this point that the Hanseatic League slowly started to coalesce, eventually influencing our isles. The League is most easily understood as a loose federation of cities that acted together in self-interest to promote trade. The Hanseatic cities developed their own
  Question: What did the Hanseatic League exchange other than commodities?
  
   (A) Animals
   (B) Women
   (C) Weapons
   (D) Knowledge
  Answer:
output: Knowledge