What type of information must always be communicated to passengers during delays?

Communication of the cause and duration of delays to passengers is essential for maintaining transparency and trust. When passengers are informed about why a delay is occurring, it helps to alleviate uncertainty and frustration. Providing the duration of the delay allows passengers to make informed decisions about their travel plans, such as whether to wait for the train or seek alternative transportation.

This practice aligns with customer service principles, where keeping passengers updated promotes a positive experience even in the face of disruptions. In contrast, options such as advertising material, circulation details, or train merchandise opportunities do not address the immediate concerns and needs of passengers waiting for their service; therefore, they are not priorities during a delay situation.