Which of the following economic elements best set apart the postclassical era from any time before it?
A. International trade spread farther than ever before.
B. Human societies first divided themselves into different classes.
C. Coin currency was used for the first time.
D. Farmers domesticated plants and animals for the first time.
It would be that "A. International trade spread farther than ever before", since before the Postclassical era most trade was confined to relatively small areas, especially in Europe.
