President Kennedy's phrase "the bonds of injustice" refers to the social and economic oppression of the slaves' heirs. (option C)
<h3>What are "the bonds of injustice"?</h3>
First, it is important to understand the context given by the passage. President Kennedy is talking about the slaves who were freed by President Lincoln, and then he moves on to their heirs, that is, to all African Americans.
When President Kennedy mentions that those heirs are not freed from "the bonds of injustice," he means that African Americans still face social and economic oppression, that they are still not treated equally.
With the information above in mind, we can select option C as the correct answer.
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