A vessel engaged in diving operations must ensure visibility by displaying which type of lights at night?

A vessel engaged in diving operations must display an all-around light combination at night to ensure visibility. This requirement is in place to alert other vessels of the diving activity and to signal that the area is under special conditions, requiring attention from other mariners.

The all-around light serves a critical function by providing visibility in all directions, which is essential for safety during diving operations. It indicates to others that there are divers in the water and promotes caution while navigating in proximity to the diving vessel. By employing this light configuration, the diving vessel enhances the awareness of nearby vessels, helping to prevent accidents.

The other types of lights mentioned do not adequately fulfill the safety needs for display during diving operations. Flashing red lights, for example, are typically used for hazards or emergency situations, and fixed white lights do not provide the necessary signals to indicate the presence of divers. Strobe lights may be useful in some contexts but are not specifically required for indicating diving operations. The combination of all-around lights is therefore the proper choice for ensuring visibility during such operations.