What does the passage suggest about the growth of urban populations in China?

The passage indicates that industrialization and trade significantly contributed to the increase in urban populations in China. This is supported by the historical context in which China's rapid industrial development and expansion of trade networks led to greater job opportunities in urban areas, thus attracting more people from rural regions.

As cities became centers of manufacturing and commerce, the economic opportunities provided by industries and enhanced trade connections played a crucial role in the urbanization process. This dynamic reflects broader trends observed in many countries during periods of industrialization, where the influx of labor into cities from the countryside is a common occurrence driven by economic factors.

Other options fail to capture the multifaceted reasons behind urban growth. Agricultural practices alone would not account for the rapid urbanization without considering the effects of industrialization and trade. A suggestion of stable urban populations contradicts historical trends of growing cities during periods of economic expansion. Finally, attributing urban development solely to trade routes overlooks the critical impact of industrial growth, which also played a significant role in transforming cities into vibrant economic hubs.