For #8, do you mean what language other than German is the most common *natively* spoken? I was obviously suspicious that less than 1.8% of Germans spoke English, and sure enough – 56% of them do. You should probably change the wording, since as the question stands now, English is definitely the correct answer. ~~ • ~~ Great quiz, by the way; I'm sorry it wasn't featured!
Number 19 is kind of tricky question - maybe not good for this. It gave black - red - yellow for first option for me so i did not even read the rest because first was "right". Otherwise good quiz.