Before 1939, nazi concentration camps mostly held people who were

The choices were: 
A) uneducated
B) foreign prisoners of war
C) Jewish
D) political dissidents and anti-socials

The answer is d.
Although killing all the Jews was one of its goals, most of the people who were in the concentration camps are political prisoners; Soviets, Poles, Gypsies, Homosexuals, people coming from different religions.

The answer is a c b d a c b d