A - a man who found the wrong country (referring to Christopher Columbus who thought he reached India but discovered America instead)B - two continents (referring to Amerigo Vespucci who realized North and South America were two separate continents)C - two men who travel west (referring to Lewis and Clark who led the first westward expedition of the US)D - a man who went to the coldest continent (referring to Roald Amundsen who was a famous explorer of Antarctica)E - the captain who discovered the smallest continent (referring to Roald Amundsen who was a famous explorer of Antarctica)Therefore, the extra theme is 5) the biggest city of the continent.