With such huge increases in population, why has there not been a direct and equivalent increase in urban development (i.e., why is it such a small proportion of habitable land use)?
a.Many people can live in small spaces, such as high rises in cities.
b.Habitable land is already being used for livestock and crops.
c.People want to live close to where they work, which is usually the city or suburbs.
d.There is not enough habitable land left for further urban development.
