Answer:
food production became more difficult
Explanation:
If I am not wrong the answer has to be D the land along the Indus River Valley
cut military supplies worldwide
cutting armaments so much that no nation has the resources to attack any others.
Mongols favored trade even before Ghenghis khan, they hunted/herded very few were weapon makers or potters/weavers, many items they needed to living had to be traded. As Ghenghis khan rose to he realized the Mongol army was gonna need many things for battles. To facilitate trade Ghenghis offered protection to merchants that came from east and west, offered higher status for merchants allowed by the Chinese or Persians who despised trade and traders.
