Final answer:
Kublai Khan is most associated with the expansion of trade and cultural exchange, as he continued to engage in trade and foster relationships despite internal challenges within his empire.
Step-by-step explanation:
The conclusion supported by Kublai Khan's actions is Option 2: Expansion of trade and cultural exchange. Despite the fragmentation within the Mongol Empire, trade continued to be a significant aspect under Kublai Khan's rule. Both Chinggis Khan and his successors like Kublai Khan acknowledged the importance of trade as a means for peace and economic prosperity.
While Kublai Khan did experience issues in maintaining a unified empire and faced challenges from his Chinese subjects, he did not espouse isolationism but rather continued to engage in trade and recognized its benefits. The Yuan Dynasty under Kublai continued with the flow of trade, albeit with less wealth being produced compared to earlier periods of Mongol dominance.
Furthermore, Kublai Khan's willingness to embrace aspects of settled life showed a departure from traditional nomadic ways, indicating an openness to cultural exchange and integration, thereby fostering continued trade relationships.