The significance of the transcontinental railroad lies in its role in connecting the eastern and western parts of the United States, facilitating the movement of people and goods, promoting economic growth, and contributing to westward expansion. Among the options you provided, however, neither accurately captures this significance.
If I had to choose the more relevant option, I would suggest focusing on the general impact of the railroad on migration and economic opportunities rather than the specific statements you mentioned. The transcontinental railroad made travel more accessible for many, not just the wealthy, and it played a crucial role in shaping the development of the nation.