The author mentions the Balkans in the passage in order to explain why ______.A．Indo－Europ

The author mentions the Balkans in the passage in order to explain why ______.

A．Indo-European languages were slow to spread in Old Europe

B．the inhabitants of Old Europe were not able to prevent Indo-European incursions

C．the use of the Old European script. declined

D．the Old European culture survived for a time after the Indo-European incursions

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