Which of these contributed to the wealth of the middle class in mesopotamia and the indus valley
trade in silk, spices, and precious metals
sale of cattle, camels, and water
slaves who worked the land
an overabundance of grain

Correct

Trade in silk, spices, and precious metals

The middle class was benefited thanks to the capture of wealth that occurred at this time. The tribute demanded at that time were precious metals, gems, silk, ivory and slaves. It should also be noted that the rich and middle classes were formed in Mesopotamia with the establishment of a royalty, a religious hierarchy, large estates and long-distance trade.

wisdom

explanation:

the fact that that the teachings on the cosmic order comes from, or through, the heart center

c or d both can be the answer