Question 31

The Correct Answer is C A vessel displaying the shape shown in illustration D010RR (a **diamond shape**) is indicating that it **has a tow that exceeds 200 meters in length**. This signal is mandated by Rule 24 of the International Regulations for Preventing Collisions at Sea (COLREGs), which specifies the lights and shapes for towing and pushing. A towing vessel displays a diamond shape where it can best be seen when the length of the tow (measured from the stern of the towing vessel to the after end of the tow) exceeds 200 meters. The towed vessel must also display a diamond shape. ### Why the Other Options Are Incorrect: **A) Is at anchor:** A vessel at anchor displays a **black ball** where it can best be seen, not a diamond shape (Rule 30). **B) Is not under command:** A vessel not under command (NUC) displays **two black balls** in a vertical line where they can best be seen, not a diamond shape (Rule 27). **D) Has a tow that is carrying hazardous cargo:** There is no specific shape required by COLREGs solely to indicate that a tow is carrying hazardous cargo. The diamond shape specifically relates to the *length* of the tow, not the nature of its cargo. (Vessels carrying hazardous cargo may display other mandated shapes or flags related to national or international codes, but not this specific diamond shape defined by COLREGs).