Which daymark has no lateral significance?

The black and white diamond daymark is the correct choice as it has no lateral significance. This type of mark is typically used to indicate a certain message or instruction that does not relate to channel direction or lateral navigation. Instead, it can serve as a navigational aid for indicating hazards or special circumstances that require special attention from mariners.

Unlike daymarks that are marked in red or green, which provide lateral guidance on the sides of navigable channels (red indicating the right side when returning from sea, and green indicating the left), the black and white diamond does not convey such directional information. Instead, it often signals that the area is a caution zone or marks a special feature or restriction, making it purely informational rather than lateral.

In contrast, the other options are all primarily used to aid in navigation by indicating the position of navigable water and channel direction, thus reinforcing their role in maritime navigation systems.