Which of the following accurately describes the entry requirement for the exhibition?

The correct option states that visitors can only enter the exhibition if they have booked online. This suggests that an online booking is a prerequisite for attendance, which often reflects modern practices in managing visitor numbers for events. Requiring an online booking can help organizers control capacity, ensure a smooth entry process, and enhance overall visitor experience by reducing queues.

The other options fail to accurately represent the entry requirements as they either imply different conditions for entry or lack the necessity for a booking altogether. For example, stating that visitors must arrive before the exhibition opens does not necessarily indicate a requirement, as it can be a general recommendation rather than a strict rule. Similarly, saying that visitors require a special pass or can enter without any prior arrangement would contradict the idea that online booking is essential for entry. Hence, the emphasis on the necessity for online bookings specifically aligns with current trends in event management and the need to streamline visitor access.