At the actual Air Law exam, just like with the other PPL exams, all questions are multiple-choice. And a lot of questions in Air Law can be answered by asking yourself one simple question: "If I were to write the laws, weighing the various interests of various parties against each other and putting safety first, how would I write this law?"
If you then add a little understanding about how aviation law is based on international treaties, and how it's embedded in the legal structure of the country you're doing your exams for (UK I assume), then you're virtually home free.