Answer:
D. The speaker logically presents the idea that all Americans need to stand together.
Step-by-step explanation:
I have chosen D because of the final sentence:
"United there is little we cannot do in a host of cooperative ventures. Divided there is little we can do—for we dare not meet a powerful challenge at odds and split asunder."
This sentence shows that united, we can do everything together. But divided, we can't do anything because we can't face something together and risk conflict.
I have looked at all the answers and read the passage well. They all seem to be logical. I have chosen D because I think it is the best answer.
Thank you for this opportunity. Good luck!