The increasing percentage of urban dwellers in more-developed countries is best explained by

Human geography.

Explanation:

The increasing percentage of urban dwellers in developed countries is best explained by human geography because the population of a region is increased due to the availability of resources. If a region has more quantity of natural resources, the population is increases just like the urban areas. There is higher availability of employment which attracts the people towards itself and the people settle in these urban areas.

the correct answer would be true friction causes the faults to slip or collide