The long term significance of Brown v. Board of Education is that it - found segregated schools to be constitutional if they were equal in quality - overturned the Plessy v. Ferguson ruling accepting segregates facilities - supported the case Plessy v. Ferguson by saying segregations was illegal - decided that each state could determine whether segregation was legal

The second one (overturned the Plessy v Ferguson ruling accepting segregated facilities) is correct

In Plessy v Ferguson the court ruled that segregation in schools was constitutional as long as the schools were equal; In Brown v The Board of Education the court's earlier decision in Plessy v Ferguson was overturned when the Warren court unanimously ruled that separate facilities were inherently unequal and that therefore segregation in schools was unconstitutional