Read the excerpt from Martin Luther King Jr's "I Have a Dream" speech

But one hundred years later, the Negro still is not free. One
hundred years later, the life of the Negro is still sadly crippled by
the manacles of segregation and the chains of discrimination.

How does King's allusion to slavery affect the speech?
King's

A. It shows the listener that Dr. King is more interested
in the history of African Americans than their present.

B. It reminds the listener of the homible conditions of
bondage and its aftereffects.

C. It tells the listener that slavery is illegal.

D. It explains why Dr. King thinks slavery is bad.