Answer:
The most important of the six essential elements of Geography, to explain the distribution of the population in the United States, is human systems.
Human systems are all the networks of human relations that cover a geographic area. They include economic systems, which are formed by groups of humans enganging in productive activities of all sorts.
In the modern era, humans tend to live in cities, specially in developed countries like the United States. The distribution of the population of the United States, that we can see on the map, is likely the result of th concentration of such human systems in the darker areas.
Explanation:
