Answer:
c. slaves lived better than Northern factory workers
Explanation:
In this extract the author arguments the bad conditions in which the workers of the northern anti-slavery states lived.
Through this, the author defends slavery because, from his point of view, slaves have no more responsabilities after their job is finished. While free workers had to continue with their personal and family cares.
It is strong point of view, however we must mention that each man is responsible for his own cares and his job, and has the right to be free.