C'mon. Duolingo accepts "What is on the german woman". That would mean something like "What has she spilled on herself". But it doesn't accept "What does the German woman have on," which asks what she is wearing.
Why is “what is the German lady wearing” not an acceptable translation for this?
What is on the German woman? - why was this not accepted. Generally one does not wear ketchup or similar things. How do you distingish between wearing and on someone. On is more inclusive because a person can have on clothes and have ketchup on them.