BOTH INTERNATIONAL & INLAND Vessel "A" is overtaking vessel "B" as shown in illustration D017RR below, and will pass without changing course. Vessel "B" is an air-cushion vessel operating in the nondisplacement mode. Which light will vessel "A" observe from vessel "B"?

Correct Answer: Option A — flashing yellow light

Rule 23(b) mandates that an air-cushion vessel operating in the nondisplacement mode shall, in addition to standard masthead and sidelights, exhibit an all-round flashing yellow light to distinguish its unique operational profile and high operating speed.