Which symbol represents a 10-fathom curve?

Correct Answer: Option A — ____ . _____ . ____ . ____

Chart depth contours utilize specific line dashes and dots to denote fathom curves per NOS standards. The 10-fathom curve is represented by a single dash followed by one dot (____ . ____), distinguishing it clearly from deeper or shallower contour intervals on nautical charts.