Maxwell works for the u. s. census bureau to keep track of urban masses in the united states. he uses to divide the country into cities of at least 50,000 people and the urbanized areas linked to them.

Settlement hierarchy for classifying urban areas.

Explanation:

A settlement hierarchy is a way of arranging the settlements on the basis of the population and other criteria as the size of the settlement can be misleading and thus settlement hierarchy is based on the density of the settlements as an extreme density will be one billion people and will lie in an Ecumenopolis, while a high density will be located in megalopolis and a conurbation. Medium-density will be 300,000 that live in a large city and 100,000 and 300,000 people in a medium city, similarity the low density will include the suburb and a large town will have a population of 10,000 to 100,000, and while a town will have a population of 1,000 to 10,000 persons.

D. a mountain abd are made by volcanos and tectonic plates

B  maybe the answer hoped it