Because economy within a certain region will be heavily depended on what resources that are available in that region.
Since the Arabian Pennisula do not possess a good climate to produce agricultural products, it's almost impossible for agricultural sector to flourish in this region, and therefore they focused their economy on things such as oil, silk, zaitun, etc.
C. Aryans
The Aryans had introduced South Asia to a system of castes with the intention of controlling the local population.
Answer: C) Nomads
Explanation: Before settling in Mesoamerica, the Aztecs started out as a nomadic tribe in northern Mexico.
Answer:
The plan anticipated that the Cuban people and elements of the Cuban military would support the invasion. The ultimate goal was the overthrow of Castro and the establishment of a non-communist government friendly to the United States.
Explanation:
Maurya Empire and Gupta Empire are the most significant but there has been more than that.
Hope this helps!