The correct answer is A. The questions that you know a lot about so you can then focus on the more difficult ones.
Step-by-step explanation:
In an essay test you are required to write essays or answers with the same structure of an essay, this implies essay tests are more challenging than other types of tests; also, these require writing abilities rather than only knowledge about some topic. Due to this, it is recommended if possible to solve the question you know more about, this guarantees you spend a short time in questions that are easy for you and later you focus on more difficult questions; also if you begin by this questions they can act as a warm-up in terms of writing and vocabulary and this would help you with more difficult ones. Thus, it is better to answer first "the questions that you know a lot about so you can then focus on the more difficult ones".