The categories from left to right are highest population, largest area, largest population density, largest city, longest coastline, and longest border (by land).
Pick the biggest place from left to right FOR EACH CONTINENT. There are decoys in this, so you must pick the correct answer. Cities are by metro areas, and Russia counts for both Europe and Asia. If a border is between two continents, then it applies for the continent where it is the longest border. Dependencies such as Greenland count (Greenland counts for Europe). *Cities of Turkey west of the Bosphorus Strait count toward Europe. The category headings are not for you to touch.