The correct answer is A) Stay clear, the other vessel is maneuvering with difficulty. The shapes shown in illustration D006RR indicate that the other vessel is restricted in its ability to maneuver, such as a vessel engaged in dredging, diving operations, or other work limiting its maneuverability. In this situation, the proper action is to stay clear of the restricted vessel, as it may not be able to take evasive action or give way to other vessels. The other answer choices are incorrect because stopping and sounding passing signals (B) is not the appropriate action, maintaining course and speed (C) could lead to a collision, and the vessel is not necessarily in distress (D) - it is simply restricted in its ability to maneuver.