What is the primary purpose of the declination diagram on a map?

• A. To differentiate and convert an azimuth between true north, grid north, and magnetic north
• B. To indicate scale on the map
• C. To show contour intervals
• D. To display political boundaries

Answer: (C)

The declination diagram shows how three north references relate to each other: true (geographic) north, grid north on the map, and magnetic north. It provides the magnetic declination value and the angle between grid north and true north, so you can convert bearings between compass (magnetic) readings and the map’s grid or true bearings. This lets you align your compass with the map and navigate accurately.

It's not about map scale, contour intervals, or political boundaries, which are shown elsewhere on a map.