Source 1 Over 150 years ago, Abraham Lincoln and Stephen A. Douglas held seven debates as they campaigned for a Senate seat in Illinois. The debates focused on the issue of slavery and its expansion into the territories. Douglas helped overturn the prohibition on slavery in the territories of Kansas and Nebraska with the Kansas-Nebraska Act. Referred to as popular sovereignty, it meant that citizens in Kansas and Nebraska, not the federal government, could determine whether slavery should be allowed to exist in these territories.

Source 2

That is the real issue [with the question of slavery]. . . . It is the eternal struggle between these two principles — right and wrong — throughout the world. They are the two principles that have stood face to face from the beginning of time; and will ever continue to struggle. The one is the common right of humanity and the other the divine right of kings. It is the same principle in whatever shape it develops itself. It is the same spirit that says, "You work and toil and earn bread, and I'll eat it." No matter in what shape it comes, whether from the mouth of a king who seeks to bestride the people of his own nation and live by the fruit of their labor, or from one race of men as an apology for enslaving another race, it is the same tyrannical principle.2

—Abraham Lincoln, during the seventh debate with Stephen A. Douglas

Which statement describes a difference between source 1 and source 2?

Answers A.
Source 1 is an example of bias, while source 2 is an example of historiography.

B.
Source 1 is a secondary source, while source 2 is a primary source.

C.
Source 1 is an example of historiography, while source 2 is an example of bias.

D.
Source 1 is a primary source, while source 2 is a secondary source.