Respuesta :
Darius was the first to use standardized coinage. By doing this, it gave the entire empire a common currency, which made it easier to undertake trade and commerce. With the ability to standardize commerce, the empire and all its cultures could be brought together easier.
One way that Darius united the Persian empire was that he standardized coinage and other aspects of the Persian economy. Option C is correct.
Darius I was the third Persian King of the Achaemenid Empire. His reign protracted 36 years, time in which the Persian Empire reached its peak.
Darius stretched the borders of the empire, which reached the Indus river and included the rich provinces of modern day Pakistan into the Persian Empire.
He created a fairer traiding system.