The correct answer is 2) Building a complex road system in communication and control.
The statement describes an accomplishment of the Persian empire is "Building a complex road system in communication and control."
Of of the most powerful empires ancient history has ever witnessed is precisely the Persian Empire. Under the rule of King Darius, the Persian Empire lived its peak moments. Darius troops conquered many states and expanded the Persian territories in Eastern Europe, the Middle East, and North Africa. The empire had the capacity to build a complex road system that allowed it effective communication between the territories and control them.