Final answer:
Megalopolises are considered functional regions due to their concentration of economic activity and economies of scale, offering abundant customers, workers, and specialized goods. Yet, diseconomies may arise from high density, such as congestion and pollution. Situation factors also contribute to the competitive advantage and growth of these large cities.
Step-by-step explanation:
Many megalopolises or megacities fit the definition of a functional region because they provide a concentration of economic activity that brings about economies of scale. These cities offer businesses a large customer base, which allows them to produce goods and services efficiently. Additionally, megalopolises have a substantial workforce and a network of suppliers, which facilitate easy hiring and procurement of specialized inputs.
However, there are limits to the benefits of such concentration, as high population density can lead to diseconomies such as traffic congestion, pollution, and increased crime rates. Beyond a critical threshold, these negative aspects may outweigh the efficiencies gained from economies of scale.
Moreover, the situation factors like a city's central location in trade and industry give it a competitive advantage that aids in its growth. So, while megalopolises offer high-order goods and services that may not be found in smaller cities or rural areas, there is a balancing act between the benefits and drawbacks of such urban concentrations.