How did public schools in the North differ from those in the South?

A) Unlike southern schools,northern schools had all been integrated by the beginning of the twentieth century.
B) Despite a few holdouts,almost all northern elementary schools were integrated,though secondary schools generally remained segregated.
C) Most northern states maintained segregated elementary schools,though a number had integrated high schools or provided separate but equal high schools to black students.
D) Northern public schools did not differ substantially from southern ones; they were almost all segregated and invariably provided black students with substantially inferior facilities.