Which of the following Physicists aided Nazi Germany in their production of a nuclear weapon?

The story behind the answer

Werner Heisenberg is correct because he led Nazi Germany’s Uranium Project (Uranverein), which researched nuclear fission and explored the feasibility of reactors and potential weapons. Though Germany never built a bomb, Heisenberg directed key theoretical and experimental work under the regime. His role remains debated—some argue he misunderstood critical calculations or deliberately slowed progress—but he undeniably headed the German effort.

Context check: Albert Einstein fled Nazi Germany and co-signed the Einstein–Szilard letter that helped spark the U.S. Manhattan Project; John von Neumann also contributed to the Manhattan Project; Max Planck stayed in Germany but did not work on nuclear weapons. Memory tip: link Heisenberg’s Uncertainty Principle to the “uncertain” success of Germany’s bomb program—Heisenberg equals Germany’s uncertain bomb quest.