This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.

Passage: Ehrlich's approach of systematically varying the chemical structure of synthetic compounds and measuring the effects of these changes on biological activity was pursued broadly by industrial scientists, including Bayer scientists Josef Klarer, Fritz Mietzsch, and Gerhard Domagk. This work, also based in the testing of compounds available from the German dye industry, led to the development of Prontosil, the first representative of the sulfonamide class of antibiotics. Compared to arsphenamine, the sulfonamides had a broader spectrum of activity and were far less toxic, rendering them useful for infections caused by pathogens such as streptococci. In 1939, Domagk received the Nobel Prize in Medicine for this discovery. Nonetheless, the dramatic decrease in deaths from infectious diseases that occurred prior to World War II was primarily the result of improved public health measures such as clean water and less crowded housing, and the impact of anti-infective drugs and vaccines was significant mainly after World War II. Question: Who is responsible for creating Prontosil?
Josef Klarer, Fritz Mietzsch, and Gerhard Domagk