Answer:
D-They were holding centers where Jewish people lived until they were sent to concentration camps.
Step-by-step explanation:
During the Holocaust, the creation of ghettos was a key step in the Nazi process of brutally separating, persecuting, and ultimately destroying Europe's Jews. Jews were forced to move into the ghettos, where living conditions were miserable. Ghettos were often enclosed districts that isolated Jews from the non-Jewish population and from other Jewish communities.