In relation to urban growth, what does the term "megacity" refer to?

The term "megacity" specifically refers to a city whose population exceeds 10 million people. This classification highlights the significant scale and urban density of such cities, which often have complex social, economic, and infrastructure challenges due to their large populations. Megacities can be found across the globe and are often seen in developing countries where rapid urbanization has led to explosive population growth.

The other options describe different concepts. Cities with extensive green spaces focus more on sustainability and livability rather than sheer size. The idea of a city focused on rural development usually pertains to smaller towns or cities that integrate rural agriculture or community initiatives rather than urban sprawl. Lastly, a small urban center with limited resources does not meet the population criteria to be classified as a megacity, as it contrasts with the concept of megacities being densely populated urban areas.