The answer is B because the supporters of a southern transcontinental railroad supported the purchase of the land that means it was for those supporters.
Slavery<span> was practiced in some parts of Africa, Europe, Asia and the Americas for many centuries before the beginning of the </span>Atlantic slave trade<span>. There is evidence that enslaved people from some African states were exported to other states in Africa, Europe and Asia prior to the European colonization of the Americas.</span>