This was a weird phrasing where I could say, until you clean up your room, you cannot have dessert. But I also could have said, not until you clean up your room, can you have dessert? They would mean the same thing. The third sentence gives us the word essential, which is a synonym for necessity. So I would ask myself, all right, what's the required thing in this sentence? If you're telling me that students' capability to make their own decisions is essential, it's required, then I know that idea goes on the right side of the arrow.