The correct answer is segregation and civil rights.
An example of this would be the Brown vs. Board of Education case. In this Supreme Court case, the Brown family sued the Topeka Board of Education. This is because this school district had segregated schools, resulting in members of the Brown family having to attend a further away all black school rather than the high school closest to their home.
The Brown family sued and their lawyer, Thurgood Marshall, argued that segregated schools was a clear violation of the 14th amendment. More specifically, the family argued this was a violation of the Equal Protection clause. The Supreme Court agreed with the family, stating that "separate but equal" was inherently unequal. This began the end of segregation in public schools.