The correct answers are A) the development of nuclear reactors and D) the movement of the planets.
Albert Einstein's work contributed to the development of nuclear reactors and the movement of the planets.
Everybody knows that Einstein was a genius. A special man way beyond his time. He is known for the development of the relativity theory, the theory of photoelectric effect, the Unified Field theory, and the study of the orbit of the planets. The Big Bang Theory was not attributed to him, but Georges Lemaitre in 1927.