True, and citypopulation.de does list it as a separate "urban area" with a population of 1763336. If the quiz is going to count "agglomerations" rather than "urban areas", it should say so.
I mean, if Scotland weren't part of the UK, it would be odd for them to have had a referendum on independence from the UK in 2014 (which was unsuccessful).
Neptune777, you entirely miss Antimony's point. He is kind-of correct since Tanger is what it's called in French, the colonial language. Tangier (or sometimes Tangiers) is an English term, not generally used locally. The alternatives you gave are simply mis-spellings; Antimony's is not.
https://en.wikipedia.org/wiki/United_Kingdom
Then I thought Madrid was further north than Barcelona.
Clearly I don't know Spain as well as I thought.