The correct answer is B.Whitman wrote it years after the death of Lincoln because it says that this dust was once a man, and that means that he is talking about Lincoln's ashes, and that means that they cremated Lincoln and so this means that Lincoln has been dead for a while.
B. Whitman wrote it years after the death of Lincoln
Hope this helped.
Because he doesn’t want to
I believe it may be C or D, but am not quite sure since there is no provided background knowledge (the poem itself)