The correct answer needs to be: "Are you a tourist?"
"Are you a tourist" is correct. However, people do say things like "You are a tourist?" It works when said with a tone of disbelief.
In english we put the "Are" ate the beginning like: "are you a tourist?"
Most of the time yes. But we can also just use a rising tone/question mark in many contexts.
Yes the corect answer should be are you a tourist