You are underway on course 328°T when you sight a buoy broad on your port bow. You are in the best navigable water if the buoy __________.

Correct Answer: Option A — exhibits a light with the characteristic of VQ(3)5s

Under IALA-A, a buoy with a VQ(3)5s light is an East Cardinal mark. Cardinal marks indicate the deepest water lies to the named side of the buoy. Since you are on course 328°T, passing to the east of an East Cardinal mark places you in the safest navigable water.