Answer:
C. the T-4 program
Explanation:
T-4 program was a program undertaken by the Nazis where subjects died of involuntary euthanasia.
Euthanasia is the act of taking a life as a relief to suffering.
T-4 stands for Tiergartenstraße 4 the street address where the personnel involved in the program were recruited.
Patients that were incurable were selected by the doctors and given a mercy death (euthanasia).
275,000 to 300,000 people were killed between 1939 to 1945
