Urbanization is
a. the construction of tall buildings.
b. a reduction in the population.
c. the concentration of the population in rural areas.
d. the concentration of the population in cities.

The correct answer is D) The concentration of the population in cities.

Urbanization involves the process of having thousands (or millions) of people move from the country side to the city. Usually, a period of rapid urbanization is caused by an increase in the amount of jobs avaliable in cities. This is definitely the case in American history, as millions of people moved to the cities during the 1920's due to the increased amount of factory jobs available.

D - the concentration of the population in cities.

Explanation:

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answer; ///was   constructed according to a mathematical formula;

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