What does the lifesaving signal indicated by a horizontal motion of a white light or white flare mean?

Official USCG Answer & Rule Citation

Correct Answer: Option D — All of the above

International lifesaving distress signals specify that a horizontal motion of a white light, white flare, or flag ashore or afloat universally commands 'Avast hauling', indicates 'Negative', and warns that 'Landing here highly dangerous'.

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