Answer:
Civil Disobedience
Step-by-step explanation:
According to the given excerpt from "Letter from Birmingham Jail", Martin Luther King expresses his opinion about what he calls just and unjust laws and how he would obey the just laws, but disobey the unjust ones, because they are "no law at all".
Therefore, the type of action against unjust laws is Dr. Martin Luther King Jr. supporting in this passage is civil disobedience.
This is because, civil disobedience simply means defiance to authority or laws.