At the beginning of act two, scene two, there is a conflict between George and Beneatha after they get home. They have dated many times before, and when they were out this time, he tells her that he expects to have a more physical relationship with her, revealing his thoughts about education, that he sees it only as a way to get money.
When he tried to kiss her at the couch while she was trying to have a conversation telling him about her dream of becoming a doctor, she moved away and refused to kiss him. George gets angry saying that "he expects women to appear sophisticated but not to express sophisticated opinions" (C) as she's been doing many times, calling her moody and her thoughts stupid. Beneatha resolves it by ending the relationship calling him a fool. He wouldn't take her seriously and she could not change his mind deciding he is not the man for her.
“There are those who are asking the devotees of civil rights, ‘When will you be satisfied?'”
I think this is the correct answer because Matin Luther King Jr. is making reference to those people who question the devotees, in other words the followers. To the opponents of King's ideas, it seems that the devotees will never be satisfied as they are allways fighting and asking for more. That is the reason they ask them "When will you be satisfied?" The opponents don't perceive the end of their demands.
Martin Luther King asks his followers to fight for things that at that time may have seem imposible, that is the reason the expectations seem high.