The best comparison of the rhetorical devices used in the passages is:
Ain't I a Woman? employs a rhetorical question, while the Declaration of Sentiments uses anaphora.
In Sojourner Truth's speech, the phrase "Ain't I a Woman?" serves as a rhetorical question that emphasizes her argument for the recognition of women's rights, particularly for Black women. Meanwhile, the "Declaration of Sentiments" by Elizabeth Cady Stanton employs anaphora with the repetition of "that" at the beginning of multiple clauses to emphasize their claims about equality and rights.