Final answer:
Persia's network of public roads, particularly the Royal Road, improved communication and trade across the empire, safeguarded by troops which benefited political control and economic prosperity.
Step-by-step explanation:
Persia's network of public roads, particularly the renowned Royal Road, was pivotal in enhancing the efficiency and cohesion of the empire. These roads facilitated improved communication and trade across the vast stretches of the empire. The robust communication system included scribes, mounted royal messengers, waystations, and inns, ensuring that messages could be quickly and reliably conveyed throughout the empire. The strategic placement of troops along the roads enhanced safety and security for travelers and goods. Efficient communication and the movement of goods were essential for maintaining centralized control and supporting long-distance trade, which in turn helped the Persian Empire thrive both politically and economically.