Choice A is the best answer. In Passage 2, Grimké makes the main point that people have rights because they are human, not because of their gender or race. This is clear in lines 58-60("Human... nature"), when Grimké states that "human beings have rights, because they are moral beings: the rights of all men grow out of their moral nature" and lines 65-68("being...To"), when Grimké writes, "Now if rights are founded in the nature of our moral being, then the mere circumstance of sex does not give to man higher rights and responsibilities, than to woman."
Choices B, C, and D are incorrect because Grimké primarily emphasizes that all men and women inherently have the same rights ("rights are founded in the nature of our moral being," lines 65-66,"being...the"). Her central claim is not that men and women need to work together to change society (choice B), that moral rights are the distinguishing characteristic separating humans from animals (choice C), or that there should be equal opportunities for men and women to advance and succeed.