Your tank vessel is fully loaded to the marks, and you find that she is down slightly by the head. Which of the following choices would be the best action to take to trim the vessel slightly by the stern?

Correct Answer: Option C — shift cargo aft

Shifting existing cargo aft changes trim without altering the vessel's total deadweight or immersion marks. Adding ballast increases draft, loading more cargo may exceed deadweight limits, and shifting ballast forward worsens the trim by the head. Cargo shifting is the precise operational remedy for draft correction.