The correct answers are A) ethnicity and C) religion.
Ethnicity and religion have been serious causes of division among the nations of Eastern Europe.
Eastern Europe has been the stage of many conflicts, even wars due to race, ethnics and religion differences. Let's just remind the Bosnian War is Bosnia Herzegovina from 1992 to 1995, as part of the Yugoslavia separation. The Government of President Slobodan Milosevic and the Yugoslav People's Army wanted to secure ethnic Serb land and the most questioned ethnic cleansing that caused the death of thousands of people.
