The statement that best describes the effect of the bubonic plague on the Mongol territories is:
B. The bubonic plague politically weakened the divided territories and made them easier to overthrow.
The bubonic plague contributed to the decline of the Mongol Empire by exacerbating internal divisions, creating instability, and weakening political control, which made it easier for uprisings and rival powers to challenge Mongol rule. While the plague did have various effects on trade routes and interactions with Europe, the primary impact in terms of political power and control aligns with option B.