Which is the best description of stephen douglas's stance regarding slavery during the lincoln -douglas debates of 1858

The main theme of the Lincoln–Douglas debates was slavery, particularly the issue of slavery's expansion into the territories.

Douglas defended the doctrine of popular sovereignty, which meant that the people of a territory could decide for themselves whether to allow slavery. His Kansas–Nebraska Act of 1854 had already repealed the Missouri Compromise's ban on slavery in the territories of Kansas and Nebraska and replaced it with this doctrine.