Answer:
B) the separation between the Orthodox Churches in the East and the Roman Catholic Church in the West
The reason why no–one really knows why he was killed is that there is no agreement about who was behind the murder, who pulled the trigger or triggers, or even how many triggers were pulled. And the reason why there is no agreement about many of the basic facts of the JFK assassination is that the case was never seriously investigated.
The amendment that ended slavery would be the 13teenth amendment