The Republic was written by Plato. The correct option among all the options given in the question is the third option.Since the middle of the nineteenth century, The Republic written by Plato has been the most popular and widely read dialogue. The Republic has been considered by many as one of the greatest works of Plato. Plato was a great mathematician and philosopher of the Classical Greece era. Two great students of Plato that became famous were Socrates and Aristotle.