Final answer:
Approximately 1,000 enslaved individuals managed to escape per year out of a total of 4 million in the 1850s. The Underground Railroad played a significant role, and Harriet Tubman was one of the many who achieved freedom through this network. The correct answer is option d.
Step-by-step explanation:
By 1850, the South was losing perhaps 1,000 runaways a year out of its total of some 4 million slaves. The actual number of freedom-seekers who were not captured within a year of escaping was very low, with estimates suggesting no more than one thousand per year in the early 1850s. Many of these individuals stayed in the South, blending in with free Black communities in urban areas. Despite the relatively small number of escapees, the Southern states feared the influence of the Underground Railroad, a network that provided assistance to those seeking freedom from slavery. Harriet Tubman is one of the notable figures within that escape network. The enactment of the Fugitive Slave Act in 1850 further increased the risks for runaway slaves, leading many to seek refuge in Canada, where slavery had been abolished.