The scientific method as we understand it today was significantly developed during the Renaissance period, but Aristotle is often credited with laying foundational elements of this process in ancient times. He emphasized empirical observation and logical reasoning in his studies of the natural world.
While Archimedes made significant contributions to science and mathematics, and En Hedu'Anna is known as one of the earliest poets and writers, it is Aristotle who is most commonly associated with early forms of the scientific method.
So, the best answer from the options provided would be Aristotle.