A.north side of the markB.west side of the markC.east s……

单项选择题A buoy，being a shape of cylinder and with red group flashing，shows that it is（）.

A.left-side buoy
B.right-side buoy
C.a buoy of safety
D.a buoy of danger

单项选择题A buoy with a composite group-flashing light indicates a(n)（）.

A.anchorage area
B.fish net area
C.bifurcation
D.dredging area

单项选择题A buoy marking a wreck will show a(n)（）.

A.white light FL (2) and a topmark of 2 black spheres
B.occulting green light and may be lettered
C.yellow light and will be numbered
D.continuous quick white light and may be numbered

单项选择题A buoy having red and green horizontal bands would have a light characteristic of（）.

A.interrupted quick flashing
B.composite group flashing
C.Morse (A)
D.quick flashing

单项选择题A bold reef is a reef（）.

A.with part of it extending above the water
B.that can be detected by water turbulence
C.that drops off sharply
D.perpendicular to the current