Question

us urban areas over 1,000,000 in 1920
population density: 1920 to 2010

cities became more spread out after 1920 due to the automobile.
cities became more crowded after 1920 due to lack of transportation.
people owned fewer cars after 1920 because they were more expensive.
there were more cities in america after 1920 because of immigration.

Explanation:

The bar graph shows population density (people per square mile) of large US urban areas declining steadily from 1920 to 2010. This urban sprawl (lower density, more spread-out cities) is linked to the rise of the automobile, which allowed people to live farther from city centers. The other options are incorrect: cities became less crowded (not more), car ownership rose (not fell) as cars became more accessible, and the graph measures density, not total number of cities.

Answer:

A. Cities became more spread out after 1920 due to the automobile.