The correct answer is option B- a defensive alliance of Greek city-states led by Athens
The Delian League was a defensive alliance of Greek city-states led by Athens, formed after the Persian Wars in the 5th century BCE. Its primary aim was mutual protection against Persia, but it evolved into an Athenian-dominated empire. This eventual control led to significant conflicts with other city-states, particularly during the Peloponnesian War.
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