Which of the following listed documents must you have with you, if you want to drive a cross-border passenger bus within the EU?

You answered correctly. When driving a cross-border passenger bus within the EU, you must carry the EU passenger waybill. This document is required for international passenger transport to show trip details and ensure compliance with EU regulations. The personal log-book is not mandatory for this purpose, and “no particular documents” is incorrect because the waybill is explicitly required. Always make sure you have the EU passenger waybill with you when undertaking such trips.