Question 755Navigation General

The correct answer is B) a tropical cyclone south of your vessel. The description of the weather conditions, specifically the long-period swell approaching from the south, indicates the presence of a tropical cyclone or hurricane south of the vessel's location. Long-period swells are a characteristic of tropical cyclones, as they generate large, low-frequency waves that can travel long distances. The relatively low frequency of the swell crests, about four per minute, further supports the presence of a tropical cyclone, as they typically have a slower wave period compared to other weather systems. The other options are incorrect because a warm front (A) would not typically generate such long-period swells, and an extra-tropical cyclone (C) or a hurricane (D) heading in the vessel's direction would likely be accompanied by other weather indicators, such as changes in wind direction and barometric pressure.