Correct. The answer is a. The author’s main point in this section is that, in the last decades of the 1800s railroads transformed the United States’ economy, pioneering a model for big business, creating enormous wealth for investors, and stimulating the growth of other new industrial enterprises.
Incorrect. The answer is a. The author’s main point in this section is that, in the last decades of the 1800s railroads transformed the United States’ economy, pioneering a model for big business, creating enormous wealth for investors, and stimulating the growth of other new industrial enterprises.