Final answer:
Most densely populated areas have rivers and/or access to waterways due to urbanization and economic development. Rivers and waterways provide freshwater, transportation routes, economic activities, and fertile land for agriculture.
Step-by-step explanation:
The observation that most densely populated areas also have many rivers and/or access to other waterways can be explained by the concept of urbanization and economic development. Rivers and waterways have historically played a crucial role in the growth of cities and human settlements. They provide a source of freshwater, transportation routes for goods and people, and can support various economic activities such as trade, fishing, and agriculture. Additionally, rivers and waterways often contribute to the formation of fertile land, which is well-suited for agriculture and attracts human settlements.
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