Ruling the Byzantine Empire and providing the "bubonic plaque" or "Justinian's plaque".
Answer:
By undermining the authorities of the European authorities.
Answer:
I want to say the third answer.
Explanation:
We see in the map that the trade routes go from the European area to the China area.
It can't be A since we see that the routes go along the border of India, so it can't be both India and the Middle East.
I don't think it can be B because we don't see as much empires made by European forces in Africa, and these empires weren't competing with the Mongols, since the Mongols could easily take over their empires.
It can't be D since we don't see the trade routes go through the ocean to the far east, and the silk road never made it to North America and South America.
Answer:
Nile river?
Explantation: Its the only thing I could think of matching that statement