Answer:
Such prisoners, like the European Jews who were murdered upon arrival in the gas chambers at the killing centers, were never officially registered as prisoners, but were killed usually within 24 hours of arrival. Recognizing the increasing numbers of these small-scale killing operations and because they needed an efficient way to kill prisoners who had become too weak to work, the SS authorities equipped several concentration camps with gas chambers during 1941-1942.
Step-by-step explanation: