"Who invents the train?"
Translation:Ai phát minh tàu hoả?
Yes, it should. However, sáng chế does not sound like a big innovation, in my opinion.
"Who invented the train?", and "Ai phát minh Ra tàu hỏa?" because the "phát minh" require a complement word (in this case the adverb "ra")
but xe lua means train!! I think this is a trick question, I don't like it. Toi khong thich no!