Which shape of marker shows non-lateral navigation aids?

The correct shape of marker that indicates non-lateral navigation aids is the diamond shape. This shape is used to designate specific areas where boats should be cautious or where certain activities are either prohibited or restricted. Non-lateral markers provide important information about hazards, such as obstacles in the water, or indicate areas such as "no-wake" zones, swimming areas, and other regulations intended for the safe navigation of vessels.

In contrast to the diamond shape, the other marker shapes serve different purposes in navigation. The crossed diamond generally indicates a prohibition, while square markers typically provide information or instructions regarding safety or specific activities. Circle markers are often used to designate a controlled area but are not primarily associated with non-lateral navigation aids. Understanding the significance of these shapes is essential for safe boating practices and compliance with navigation regulations.