Read this line from the "What to the Slave Is the Fourth of July?"
"Are the great principles of political freedom and of natural justice, embodied in that Declaration of Independence, extended to us?"
What does Douglass imply with this question?

a. He and his listeners are of one group.
b. He and his listeners were once separate groups but are now one.
c. The Declaration of Independence does not apply to everyone.
d. Some were excluded from the Declaration of Independence in the past, but not presently.