In the process of urbanization in some areas, due to the excessive development of labor-intensive and private enterprises, urban economic construction has strongly depended on the floating population. Although the floating population has brought vitality and vitality to cities, it has increased fiscal and taxation. Income, but because their cultural level is generally low and their overall quality is not high, it has created an amazing number of small merchants and hawkers and huge "migrant workers" teams. With the continuous upgrading of industries in these regions, the demand for simple labor will inevitably increase. With less and less, the floating population will face the danger of unemployment, which will inevitably cause more serious problems, which will hinder the process of urbanization in these areas. What is the main point supported by this passage? ['The increase in the floating population has a negative effect on urbanization development in some areas.', 'Over-development of labor-intensive and private enterprises has led to an increase in large numbers of migrants.', 'The existence of a large number of low-quality migrants is not conducive to the development of urbanization.', 'Unemployment of large floating populations is a potential crisis in urbanized areas.']