.....But the point is that Cairo does not have an urban population of more than half of Egypt's population of over 100 million. Putting Cairo at 50+ million would easily make it the world's largest urban area. It's not. Nobody makes such a high claim for Cairo, except this quiz.
I don't get where they are measuring some of these populations statistics. For example, if it's city proper, Kuwait should have been broken up and therefore not considered, but if they are counting the urban or the metro population, Doha and Manama should certainly be here (with over 2million and 1million people respectively).