Answer:
The Athenian statesman during the golden age who promoted the idea of democracy was Pericles. Therefore, the correct answer is c) Pericles. He was a prominent leader in Athens from 461 to 429 BCE and played a crucial role in shaping Athenian democracy and overseeing various cultural and infrastructure projects. Socrates, Alexander the Great, and Plato were significant figures in history but did not specifically promote democracy during the golden age of Athens.