Final answer:
Stephen Douglas advocated for popular sovereignty, allowing territories to choose whether to allow slavery, and in the Freeport Doctrine, he maintained that territories could bar slavery. Thus, Douglas's position on slavery was one of opposition to its expansion, though not abolitionism.
Step-by-step explanation:
Stephen Douglas's position on slavery, based on his speech and actions during the historical period leading up to the Lincoln-Douglas debates, is somewhat complex. Douglas is best known for advocating the concept of popular sovereignty, which allowed residents of a territory to decide for themselves whether to permit slavery.
In the debates, especially in the Freeport Doctrine, Douglas maintained that despite the Supreme Court's Dred Scott decision, territories had the right to bar slavery by refusing to pass laws that protected slave property. This nuanced position undertook to satisfy Northern sentiments against the spread of slavery while not completely alienating Southern slaveholders.
Therefore, in the context of the student's question, the most fitting answer choice would be: (c) Opposes slavery. Although Douglas's stance was not that of an abolitionist and he did not oppose the institution of slavery where it already existed, his doctrine implied opposition to the expansion of slavery into new territories.
His stance against the Lecompton Constitution and his contentious relationship with southern Democrats over the issue also underscore the complexities in his position, suggesting a resistance to Southern pro-slavery pressures.