The Following Questions Refer to the Excerpt Below

The following questions refer to the excerpt below.
"…It follows,from what has been stated,that it is a great and dangerous error to suppose that all people are equally entitled to liberty.It is a reward to be earned,not a blessing to be gratuitously lavished on all alike-a reward reserved for the intelligent,the patriotic,the virtuous and deserving,and not a boon to be bestowed on a people too ignorant,degraded and vicious to be capable either of appreciating or of enjoying it."
John C.Calhoun,"A Disquisition on Government," 1849
-John C.Calhoun reveals here that many Southerners' based their arguments in favor of slavery on

A) support for the Northern labor market.
B) the economic necessity of the institution.
C) theories about racial superiority.
D) the Constitution's protections of states' rights.