Cool quiz! Are we supposed to know where they are in the world? Because there is no hints towards where they are in the world... Or is it on purpose that you don't know where they are in the world?
No, each time the 20 countries could be from anywhere and are randomly chosen for your quiz. Before I posted this quiz I tried it out on myself, and I got all 20 in 10 minutes. The 20th is the unnerving one, wondering whether you've remembered to work your way around the world thoroughly.