Good quiz, but the question "To have another country contained in its name" is really bad. There are 4 possible answers and only 1 is randomly correct (Guinea-Bissau, SoMALIa, Equatorial Guinea, South Sudan)
Could use more time, but great quiz! I also agree with GoblinOfCooz that the question about containing another country within its name should accept all four possible options.
Better still, it is ought to be a different question. If it accepted all four answers it would mess up the format, the point of being that the pool of possible answers are eliminated one at a time.
Just a suggestion, but couldn't you fix the "To have another country contained in its name" problem by changing that clue to "To have a name containing a hyphen"?
Also, Eswatini has some weird capitalization going on