Philip II and Alexander the Great were able to conquer vast amounts of territory, primarily because they __________.

Philip II strengthened Macedonia’s army with innovations such as the long-spear phalanx and effective cavalry, giving it a major military advantage. Alexander used this well-trained, well-equipped army to conquer a vast empire. The other choices do not explain their success as directly: they did not rely primarily on an alliance with Athens and Sparta or control of regional gold trade.

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