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"): It consisted of hydrogen cyanide (prussic acid), as well as a cautionary eye irritant and one of several adsorbents such as diatomaceous earth.
Relevant evidence: No