Answer
With Cattle.
Explanation
Aryan was ancient people specifically called Indo-Iranian from areas around Caspian Sea. There great influence was on the formation of ancient Indian-Iran relationship .This group of individuals existed during the times when there was no writing thus most of their history was not documented. Economically, Aryan raised cattle, sheep and goats though they also farmed crops for trade with other tribes. The most vital indicator of wealth was Cattle and the more the number of cattle possessed by a family the more wealthy the family was, thus the cattle was later made illegal to be killed because of its importance.
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