No one knows the true reason for the mysterious decline and fall of the Mayan civilization but many believe that it was because the Maya had exhausted their environment and surroundings to the point that it couldn't sustain a large population anymore. This would have caused all the Maya to abandon their cites or die off. Again this is just a popular theory of scholars but the answer is that no one really knows. All that is for sure known is that the Classic cites were soon abandoned and the Maya region collapsed. Hoped this helped.
Answer:
C
Explanation:
the Roman empire exists of France, Greece and Great Britain
Answer: Zheng He's voyages to western oceans expanded China's political influence in the world. He was able to expand new, friendly ties with other nations, while developing relations between the east-west trade opportunities. Unfortunately, the official imperial records of his voyages were destroyed.
Hope this helps :)