Question

Bosnian Serbs used violence to rid Bosnia of its Muslims. What was it called?

Answer 1

Ethnic Cleansing.

Explanation:

This kind of operation is aimed at removing a selected gropu of people that you can distinguish either for their nationality (origin, language, political orientation, etc.) or religion.
Obviously it is not the first time in history that this kind of practice was used (Armenians, North American Indians, Tutsi in Africa, Jews during WWII, Kulaks in Soviet Union, etc.) and normally it ends up in or is triggered by a civil war.