The correct answer is B) Native Americans.
The segments of the United States population that was harmed by the geographical spread of railroads were the Native American Indians.
Transcontinental Road brought many benefits to America. It connected the East of the country to the West. Railroads allowed white people to settle in the new territories of the West to fulfill its Manifested Destiny. White people prospered in new industries such as oil, cattle, and mining. Unfortunately, not everything was good news for everybody. Native American Indians Reservations were moved by the United States government. Many Indians tribes had to move to other regions of America. They were harmed by the geographical spread of railroads.