What was the ruling of the 1954 Supreme Court case Brown v. Board of Education of Topeka?

A.
Integration of public schools is up to the state government.
B.
Facilities can be separated by race if they are equal.
C.
Each school has a choice to integrate or segregate.
D.
Segregation in public schools is unconstitutional.

D. Segregation in public schools is unconstitutional.