The correct answer is A) It has protected civil rights using the Fourteenth Amendment and other laws.
The 14th amendment was one developed during the era of Reconstruction. This critical time in American history was focused on rebuilding the south and providing rights for newly freed slaves. One of the most important amendments that did this was the 14th amendment. The 14th amendment includes birthright citizenship as well as the Equal protection clause. This clause is supposed to ensure that all citizens are treated/protected equally by the Constitution.
This is why cases, like the ones mentioned your question, protect the rights of all American citizens. Its interpretation has changed constantly to include the protection of members of the LGBTQ community, individuals of different races, and individuals of different sexual orientations/preferences.