Final answer:
The subjects being compared are the writings of Harriet Jacobs and Frederick Douglass.
Step-by-step explanation:
The subjects being compared in the passage are the writings of Harriet Jacobs and Frederick Douglass. Both authors were former slaves who escaped and later became authors and leaders in the abolitionist movement. Their works are considered 'twin classics' of African-American literature, but there are differences in their structures, focuses, and perspectives, particularly regarding gender.