Final answer:
Dr. Martin Luther King Jr. considered white moderates to be a significant obstacle to racial equality, potentially more so than groups like the Ku Klux Klan, due to their preference for order over justice. The correct answer is option A. White supremacists.
Step-by-step explanation:
Dr. Martin Luther King Jr. explained that the white moderate could be more of a stumbling block to racial equality than groups like the Ku Klux Klan.
King felt that the moderate who is more devoted to 'order' than to justice, who prefers a negative peace which is the absence of tension to a positive peace which is the presence of justice, who constantly says 'I agree with you in the goal you seek, but I cannot agree with your methods,' could pose a greater challenge to progress.
These individuals, in King's view, because of their influence and number, had the potential to slow down the push for justice more than overt white supremacists.