Question: The Deutsche Gesellschaft für Schädlingsbekämpfung mbH (translation: German Corporation for Pest control), in short Degesch, is a German chemical corporation, Degesch had the patent of the infamous Zyklon B, was the trade name of a cyanide-based pesticide invented in which country in the early 1920s?
Sentence (from "Zyklon B"): The product is infamous for its use by Nazi Germany during the Holocaust to murder approximately one million people in gas chambers installed at Auschwitz-Birkenau, Majdanek, and other extermination camps.
Relevant evidence: No