The correct answer is C.
King's "Letter from Birmingham Jail," was a response a to letter published in a newspaper decrying the demonstrations for which he had been incarcerated and calling them "unwise".
In this letter, King explains what these protests in Birmingham were about and why it was necessary for him and his fellow protestors to fight for their rights, since no one, not the local leaders or the courts, would confront the issues at hand.
You have to show the text too because your answer is in the readings.