9. You - to-bring your passport to the airport tomorrow; otherwise , you might encounter difficulties during the check-in process. A)may not forget don't have to forget C)would not forget D)had better not forget E) can't have forgotten 1

The correct answer is D) had better not forget. This option suggests a strong recommendation or advice to not forget to bring the passport to the airport. It implies that forgetting to bring the passport could lead to difficulties during the check-in process.