Long after the Brown v. Board of Education decision, some states had not desegregated their schools because

The Supreme Court ruled school segregation unconstitutional in Brown v. Board of Education, but it did not give states a firm deadline to desegregate. Its later guidance called for desegregation to happen “with all deliberate speed,” which allowed some states to delay. So the correct choice is “the Supreme Court had not set a deadline for doing so.”

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