Which of the following is essential to include in all distress calls?

Including a description of the vessel in all distress calls is essential because it allows rescuers to quickly identify and locate the vessel in distress. This information typically includes the vessel's name, registration number, type, color, size, and any other distinctive features that can aid in its identification. In an emergency, time is of the essence, and providing accurate identification details can significantly enhance the efficiency of search and rescue operations.

Without a clear description of the vessel, rescuers could waste precious time searching for a craft that is difficult to distinguish from others in the area. This capability to pinpoint the distressed vessel facilitates a more effective and timely response from rescue agencies.

In contrast, while signal strength, types of navigational equipment, and sailing history may be relevant in specific contexts, they do not provide the immediate identification needed for urgency in distress situations. Focusing on the vessel's description ensures all necessary and relevant identification details are clear in a distress situation.