Which ancient civilization invented the first standardized coin-based currency system that revolutionized retail trade in the 7th century BCE?

The ancient world had sophisticated commercial systems long before modern retail. From the agoras of Greece to the forums of Rome and the bazaars of Mesopotamia, ancient civilizations developed remarkable innovations in product distribution, trade, and marketing. This trivia question explores one of history's most significant commercial developments that continues to influence modern retail concepts.

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Lydians (in modern-day Turkey)
Egyptians along the Nile Delta
Phoenicians of the Mediterranean coast
Sumerians of Mesopotamia