What that vessel is and what she is doing, from what you can see and hear. The light arcs and where their numbers come from, what each kind of vessel shows under way and at anchor, the day shapes, the whistle signals and the two meanings one short blast carries, the fog signals, and reading the aids to navigation.
Score 80% or higher to earn a certificate.
The light-pattern questions are deliberately parallel — red over red, red over white over red, green over white, red over white, white over red — because that is exactly the set people confuse with each other, and testing them apart from one another would not find the confusion.