What is the primary function of topographic symbols on a map?

The primary function of topographic symbols on a map is to represent both natural and man-made features, which provides a comprehensive understanding of the terrain and its characteristics. These symbols illustrate a variety of elements, such as mountains, rivers, roads, buildings, and vegetation, helping the map reader visualize the landscape. This is crucial for effective navigation and planning, as understanding these features enables better decision-making in outdoor environments, whether for military operations, hiking, or land use planning.

Other options listed do not encompass the full range of functionality provided by topographic symbols. For example, indicating political boundaries is just one aspect of map information, while showing elevation changes alone does not address the representation of all pertinent features. Similarly, marking routes of travel is only a small part of what topographic symbols accomplish; they serve a broader purpose by encompassing the entirety of the terrain's features.