For example, the ancient monuments at Great Zimbabwe are still consistently used as a symbol of political power in the modern nation of Zimbabwe. Great Zimbabwe, constructed between 1100 and 1450, describes the ruins of the capital of the Kingdom of Zimbabwe. At its peak, Great Zimbabwe was inhabited by more than 10,000 people. –“Civilization,”
National Geographic

Which fact from the passage would support the argument that large populations allowed civilizations to develop.

Great Zimbabwe was constructed between 1100 and 1450.
The ancient monuments at Great Zimbabwe are still used as a symbol of political power.
Great Zimbabwe describes the ruins of the capital of the Kingdom of Zimbabwe.
At its peak, Great Zimbabwe was inhabited by more than 10,000 people.