Which vessel must give way to a vessel that is not under command?

The correct answer highlights that any power-driven vessel must give way to a vessel that is not under command. A vessel that is not under command is one that, due to circumstances such as mechanical failure or crew incapacity, is unable to maneuver or take action to avoid a collision.

In maritime navigation, there are specific rules that establish the right of way to ensure safety. When navigating, power-driven vessels are generally required to take precautionary measures to avoid collisions, especially with vessels in distress or unable to maneuver. The principle behind this is rooted in the nature of power-driven vessels, which have greater control and can make quicker changes in speed and direction compared to non-powered or sailing vessels.

Other vessel classes, such as sailing vessels or recreational vessels, also have to follow right-of-way rules; however, the fundamental obligation for power-driven vessels to yield is particularly emphasized in the rules of the road since they are often larger and would have more potential to cause damage in a collision. The emphasis on power-driven vessels in this context is based on their operational capabilities and the maritime safety mandates designed to prevent collisions.