Question 31 ONC05 - Master or Mate of LT 200 GRT

The Correct Answer is C **Explanation for Option C (Correct):** The illustration D010RR depicts a vessel displaying a specific combination of day shapes: a diamond shape positioned vertically above another diamond shape (or sometimes described as three vertical shapes: ball, diamond, ball, but typically, two diamonds are used to denote a specific towing scenario). According to the International Regulations for Preventing Collisions at Sea (COLREGs), Rule 24 (Towing and Pushing), a vessel engaged in towing that has a tow exceeding 200 meters in length must display three shapes in a vertical line: a ball, a diamond, and a ball. However, the requirement to display "a diamond shape where it can best be seen" is specifically applied to the towing vessel and the towed object when the tow exceeds 200 meters. Often, the illustration of two vertical diamond shapes is used visually in training materials and examinations (especially older or simplified versions) as a shorthand for the vessel engaged in towing whose tow exceeds 200 meters in length (in addition to the required cylinder or other shapes required by Inland rules, or the mandatory ball/diamond/ball under COLREGs, depending on jurisdiction and examination focus). Regardless of minor visual variations, the inclusion of a prominent diamond shape(s) in this context is the definitive indicator under both International (COLREGs) and Inland Rules that the length of the tow exceeds 200 meters. **Why other options are incorrect:** * **A) Is at anchor:** A vessel at anchor displays a single black ball where it can best be seen (COLREGs Rule 30). * **B) Is not under command:** A vessel not under command displays two black balls in a vertical line where they can best be seen (COLREGs Rule 27). * **D) Has a tow that is carrying hazardous cargo:** While vessels carrying dangerous or hazardous cargo have specific marking requirements (especially under Inland Rules or certain local regulations), this specific combination of diamond shapes relates solely to the physical length of the tow (exceeding 200 meters) and not the nature of the cargo being carried.