Final answer:
The Mongol Empire around 1300 was approximately 4,600 miles wide from north to south, which corresponds to option D.
Step-by-step explanation:
Around 1300, the Mongol Empire was estimated to be approximately 4,600 miles wide from north to south at its peak, which corresponds to option D. This vast territory stretched from the steppes north of China, expanding across Asia, reaching as far as eastern Europe, and encompassing a myriad of cultures, ethnicities, and religions.
The Mongol armies, under the command of Genghis Khan, rose to power through their superior military strategies and their ability to conquer both nomadic and settled societies.