Sometimes, you are required to write an essay on a question that seems impossible to answer in a trilogy of books, let alone in a much shorter piece of writing. It can be done. Here's some advice on how (in addition to this).
1. Read the question carefully and make sure your thesis and argument(s) actually address the question. Really focusing on the question will often make your life easier (for a while).
2. Take a few minutes to formulate an intuitive answer to the question (or several, and then choose) and then use that as a starting point. You can do this, whatever the question is. And remember: you don’t have to give a fully comprehensive answer to all aspects of the question for all possible cases; just make a single argument that works.
3. Plan. Your. Essay. Look at the requirements and put together a logical and analytical outline with a good introduction (incl. question, thesis, road map), body (in which each paragraph makes a distinct argument), and conclusion. Preferably before you start writing.
4. Finish the full essay before the deadline and revise and re-write it. Because unless you are a truly exceptional writer, it's really hard to juggle both composition and complex thinking in the first attempt.
5. Allow yourself to be creative. Often, difficult questions are meant to be like puzzles, designed to make you think a bit outside the box. You have all the necessary pieces to solve them, but the challenge is to put these pieces together in a coherent and convincing way.