Question 452 Rules of the Road

The correct answer is A) Sound no whistle signal. In an international crossing situation, if the other vessel sounds one short blast, it is indicating that it intends to hold course and speed. In this case, you, as the vessel receiving the one short blast, should hold your course and speed as well, without sounding any additional whistle signals. The regulations do not require you to respond with any whistle signals in this scenario. The other options are incorrect because B) answering with one short blast would be redundant, C) sounding the danger signal is not the appropriate response, and D) answering with two short blasts would indicate that you intend to alter course, which is the opposite of the situation described.