In which sentence from King's “I Have a Dream Speech” does the author acknowledge those who disagree with his main argument that followers must set high expectations to succeed in their struggle for equality? Click here to read the speech.

“I am not unmindful that some of you have come here out of great trials and tribulations.”
“Those who hope that the Negro needed to blow off steam and will now be content will have a rude awakening if the nation returns to business as usual.”
“…one day, down in Alabama, with its vicious racists, with its governor having his lips dripping with the words of interposition and nullification…”
“There are those who are asking the devotees of civil rights, ‘When will you be satisfied?'”