In the early 1900's many large metropolitan areas used rail service as their mode of transportation. Throughout the twentieth century, people began using their cars and the railroads sat empty in these large cities. Today, many large cities have too many cars on the road resulting extreme traffic congestion on the highways.
To reduce the traffic problems, these cities are now looking to re-use some of the infrastructure from the old rail systems to build new light rail systems. The return to rail as a means of transportation illustrates which of the following ideas about social change?
1. Mechanical solidarity
2. Contagion theories
3. Rise and fall theories of social change
4. De differentiation