Answer: A.The road had rest stations where riders could obtain food and new horses.
Explanation: The Royal Road was the most important highway in the Persian Empire. It went from Susa to Sardis and was about 1,500 miles long. To help riders on the road travel more quickly, the Royal Road had several stations. These stations gave food and water to the riders, and they had fresh horses so that riders could continue on their way. The Royal Road allowed trade to flourish in the Persian Empire, and it allowed Persian armies to move more quickly.