A significant demographic effect of modernization involving the shift of population centers from rural, agricultural settings to cities is?

Urbanization

Explanation:

Urbanization is simply the process that involves the movement of persons from rural areas to urban areas which consequently leads to the growth of those urban areas. The rural-urban migrants usually do this, having in mind that the cities and towns seem to have better political and economic growth compared to their old rural areas and that the rural areas are said to be backward and more primitive.