SAILING VESSEL AND POWER DRIVEN VESSEL APPROACHING
If you are operating a power-driven vessel and you approach a sailing vessel, the sailing vessel will always be the stand-on vessel and have the right of way.
Here power-driven Vessel B approaches sailing Vessel A. So the sailing vessel is the stand-on vessel and will maintain its course, while Vessel B is the give-way vessel and must take early and substantial action to keep clear of vessel A.
The only time a sailing vessel is not the stand-on vessel is when the sailing vessel is overtaking a power-driven vessel.
SAILING VESSELS STAND ON WHEN BEING OVERTAKEN AND GIVE WAY WHEN OVERTAKING.