Original sentence: The genocide officially sanctioned and executed by the Third Reich during World War II, collectively known as the Holocaust, took the lives of three million Polish Jews and Poles  The extermination camps played a central role in the implementation of the German policy of systematic and mostly successful destruction of over 90% of the Polish-Jewish population of the Second Polish Republic
Edited sentence: The genocide officially sanctioned and executed by the Third Reich during World War II, collectively known as the Holocaust, took the lives of three million Polish Jews The extermination camps played a central role in the implementation of the German policy of systematic and mostly successful destruction of over 90% of the Polish-Jewish population of the Second Polish Republic