Your vessel is crossing a river on the Great Lakes System. A power-driven vessel is ascending the river, crossing your course from port to starboard. Which statement is TRUE?

Correct Answer: Option B — The vessel ascending the river has the right of way.

33 CFR 83.15(a) (Rule 15) establishes that on the Great Lakes and Western Rivers, a vessel crossing a river must not impede a power-driven vessel ascending or descending the river. The ascending vessel has the right-of-way, requiring the crossing vessel to maneuver to avoid impeding her passage.