Read this sentence from "A Letter from Birmingham Jail" by Martin Luther King Jr.:

We know through painful experience that freedom is never voluntarily given by the oppressor; it must be demanded by the oppressed.

Which statement best explains how the word painful impacts the tone of the speech?

It helps create a detached, professional tone.
It helps create a concerned, empathetic tone.
It helps create a docile, yet respectful tone.
It helps create an enthusiastic, yet dignified tone.