Sometimes foreign charts are reproduced by NGA. On such a chart, a wire- dragged, swept area may be shown in green or __________.

Correct Answer: Option A — purple

NGA chart production standards specify that wire-dragged or swept areas are highlighted in purple to provide high contrast against standard black or colored chart features. This color coding alerts the navigator to areas where the depth has been verified by mechanical sweeping, ensuring safe passage for deep-draft vessels.