Why did the number of urban centers increase in the early twentieth century? Select one:
1)
Military leaders sought to concentrate the population in urban areas.
More jobs in manufacturing and services were found in cities.
Population growth increased the need for food.
Rural areas needed more workers to grow and harvest food.

More jobs in manufacturing and services were found in cities

Explanation:

The early 20th Century was marked by an economic boom that was caused by the implementation of production method that invented during the industrial revolution.

At that time, newly opened factories tend to be found in big cities since establishing a businesses there will open more chance for the owner to established a connection/ relationship with other businesses in the area. As a result, many people all across the country decided to move to the big cities with the hope that they could improve their standard of living.