Question 4

The Correct Answer is C **Why Option C is Correct:** The description details the lights of a vessel seen from ahead or nearly ahead, specifically a towing vessel. The key identifying feature is the three white lights displayed in a vertical line, positioned above the level of the sidelights. According to the COLREGs (Rules 21-31, specifically Rule 24 - Towing and Pushing), a power-driven vessel when towing must show: 1. **Sidelights (Red and Green):** Indicates the vessel is underway. (You see these.) 2. **Masthead lights:** Two masthead lights in a vertical line instead of the usual one or two, to signify towing. 3. **Sternlight and Towing Light.** However, **Rule 24(a)(ii)** explicitly states: "when the length of the tow exceeds 200 metres, three such lights [masthead lights] in a vertical line instead of two." The vessel described is showing: * **Red and Green sidelights:** Vessel is underway. * **Three white lights in a vertical line above the sidelights:** These are the masthead lights indicating a tow of more than 200 meters. Therefore, the vessel is "a vessel towing a tow more than 200 meters astern." **Why the Other Options are Incorrect:** * **A) a vessel not under command (NUC):** A vessel not under command displays two all-round red lights in a vertical line (and sidelights/sternlight if making way), not three white masthead lights. * **B) a vessel trawling:** A vessel engaged in fishing (trawling) displays two all-round lights in a vertical line: green over white (and sidelights/sternlight if making way). * **D) a vessel underway and dredging:** A vessel engaged in dredging displays different lights depending on whether it obstructs a safe passage. If it obstructs passage, it typically shows three all-round lights in a vertical line: red-white-red. If it indicates the side on which other vessels may pass, it shows two all-round green lights on that side and two all-round red lights on the obstructed side. It would not display three white masthead lights.