Nice quiz, but for the last question I think you need to change the question as it refers to "species" whereas you sometimes treat a group of animals comprising of several species as a single "species". For example, the white rhino shown is endemic to Africa. Your answer incorrectly indicates that it is not an species endemic to a single continent. There are of course rhinos in Asia, but these are separate species to the two African species. Your were clearly looking for "rhinos" without looking at which of the five rhino species you are looking at. Nice quiz though.
I still think the 4th question is pretty misleading. "General species" isn't exactly a technical term. I'm assuming you mean all species that share the same genus are endemic to the same continent? If that's the case, I don't think it is immediately obvious. And if that isn't the case, then it clearly isn't immediately obvious.
Anyway, I enjoyed the quiz!