What type of navigation light would indicate a powered vessel?

A white all-round light is the designated navigation light that indicates a powered vessel. This light is typically used to signal the presence of a vessel that is underway, making it clear to other mariners that the vessel has propulsion capabilities. It is essential for powered boats to use this light, particularly in low visibility conditions, such as at night or during fog, to ensure safety and prevent collisions.

The implementation of this type of navigation light is standardized in international maritime regulations, which helps promote uniformity and understanding among various vessel operators. The white all-round light is visible from all directions, making it an effective signal to communicate the vessel's status as powered to other boats in the vicinity.

In contrast, the other options represent different types of navigation lights or signals that convey other information. For example, a red non-blinking light typically indicates a vessel that is either stationary or not under command. A flashing yellow light is often used to indicate special conditions or signify a temporary hazard rather than the status of a powered vessel. The green light, found on the starboard side of a vessel, indicates its direction and is part of the traditional color coding for navigation lights but does not specifically indicate a powered vessel on its own.