Final answer:
The largest increase in car ownership occurred during the 1920s, primarily due to the mass production of affordable cars like the Model T Ford. This shift transformed American society, leading to the rise of automobile suburbs and a change in urban planning to accommodate the growing number of personal vehicles.
Step-by-step explanation:
Between 1900 and 1930, the number of people who owned cars increased significantly with the largest increase in car ownership occurring during the 1920s. This period of dramatic growth in automobile possession was largely fueled by the mass production of vehicles, with the Model T Ford serving as a catalyst for making car ownership accessible to the average American. The manufacturing and popularization of the automobile not only changed transportation but also had profound effects on the American lifestyle and urban planning, leading to the development of suburbs and the restructuring of cities to accommodate the increasing number of personal vehicles.
As automobiles became more popular, various industries and infrastructures evolved to support this new mode of transport. The automobile revolutionized travel, expanded economic opportunities, and even influenced social behaviors. This era marked the transition from an urban society heavily reliant on streetcars and railways to a culture dominated by the convenience of personal cars.