The Percentage of the Population Living in Urban Areas Is

The percentage of the population living in urban areas is

A) increasing in high-income nations, but decreasing in low- and middle-income nations.
B) increasing everywhere.
C) increasing in low- and middle-income nations, but decreasing in high-income nations.
D) becoming younger because older people retire to urban areas.
E) increasing in low- and high-income nations, but stable in middle-income nations.