What effect did the Supreme Court’s unanimous ruling in Brown v. Board of Education have on elementary and secondary schools as well as universities throughout the country?

The ruling forced schools to desegregate by merging the student bodies of the formerly all-black and all-white schools.
The ruling had no effect on schools.
The ruling forced the schools to improve the education quality in those schools serving an exclusively black student body.
The ruling forced several states to stop providing education to any student regardless of color.