What is a Mercator chart and why is it preferred for coastal navigation?

• A. A Mercator projection preserves rhumb lines as curved lines, complicating plotting.
• B. A Mercator projection preserves rhumb lines as straight lines, simplifying plotting of constant bearing.
• C. A Mercator chart uses an azimuthal projection for polar navigation.
• D. A Mercator chart is best for great-circle routes.

Answer: (B)