These transportation routes represented an extraordinarily dangerous act of civil disobedience on the part of American abolitionists. Why were they created? A. They were part of the Underground Railroad, a secret and illegal plan to help slaves escape to freedom. B. They were part of the Underground Railroad, a secret method of smuggling cheap cotton to northern factories. C. They were part of the Underground Railroad, a plot to sneak enslaved workers into secret bondage in free states. D. They were part of the Underground Railroad, a series of safe houses where southern planters could keep slaves they feared would rebel.