Answer:
It extended from East Asia to the Black Sea in Eastern Europe.
Step-by-step explanation:
The Mongol Empire had its origin in the Mongolian steppe, when Genghis Khan united the nomadic tribes of Mongolia under the same banner.
From there, it spread to China, Central Asia, Persia, The Middle East (where the Mongol army destroyed Baghdad, perhaps the most important city of the world at the time), Russia, and Eastern Europe.
The Mongol Army advance was only stopped as west as Hungary.
In conclusion, we can see that the Mongol Empire stretched from East Asia to the Black Sea.