SAT English Practice Question

The passage below is adapted from a book about the history of the United States. The author is describing the role of the US Postal Service in the development of the country. The early days of the United States Postal Service were marked by a series of innovations that made it possible for people living in remote areas to keep in touch with one another. The development of the Pony Express, for instance, was a vital step in connecting the East Coast with the West Coast. The advent of the railroad allowed for mail to be delivered much more quickly. This period of innovation was vital to the growth of the United States, the author argues, because it helped to create a sense of national unity. What is the most likely reason the author uses the phrase "for instance"?

1. A.provide an example of a point previously made.
2. B.contrast two different ideas about the US Postal Service.
3. C.explain the importance of the US Postal Service’s role in the development of the country.
4. D.introduce a new argument about the US Postal Service.