How can you fail when there is only one option?
What was the problem with this question, I've just looked at it in the editor and can't see anything obviously wrong.
I was only given one word to choose from. Kind of hard to get it wrong when there is LITERALLY no wrong answer.
Oh, I see you were using the app. We have zero control over how the questions appear in the app, hopefully the next app update will fix things like this, since as you say, it is hardly teaching anything giving only one option to click on.