Schweser has a great "performance tracker" that goes with the answers; breaks down all answers per study session and per topic, and you can see how well you are doing compared to others who have taken the same test up until the same point in time.
But on the other hand, if you're doing the exam without access to the performance tracker, I guess your best option is to go back to the question to figure out which one is the correct answer. It will often be obvious when you look at it. If not - go back to the study session and hopefully it will become obvious to you.