How is the distance on a nautical chart typically marked?

The correct answer is marked in nautical miles because nautical charts are specifically designed for maritime navigation. Nautical miles are essential in this context as they correspond to the curvature of the Earth, making them particularly relevant for charting courses over large distances at sea. One nautical mile is equal to one minute of latitude, facilitating accurate plotting and navigation for vessels. This unit of measurement allows mariners to calculate distances based on the degrees of latitude and longitude, which is fundamental when navigating on a chart.

Other units like feet, meters, and kilometers may be used in different contexts such as on land or in aviation but are less practical for maritime navigation. Nautical charts rely on the nautical mile for precision in navigation due to its relation to the Earth’s geometry.