Final answer:
Zheng He's maritime activity during the Ming Dynasty can be considered a turning point in world history to a certain extent.
Step-by-step explanation:
During the Ming Dynasty, Zheng He's maritime activity can be considered a turning point in world history to a certain extent. Zheng He's massive fleet and exploration of the Indian Ocean region, as far as Africa, played a significant role in expanding Chinese influence and establishing a tributary system. However, it is important to note that the extent of Zheng He's voyages and their long-term impact on world history is debated among historians.