Final answer:
Tensions between the Bedouin and the merchant class were caused by economic competition over trade routes and growing social class disparities.
Step-by-step explanation:
The strained relations between the Bedouin of the desert and the merchant class of the towns can largely be attributed to economic competition over trade routes and the disparity in wealth accumulation. This tension arose as towns grew richer and the merchants gained wealth, which led to increased social class disparities. The Bedouin, who were traditionally nomadic, found their way of life and economic interests clashing with the settled, wealthier merchant class who controlled and profited from the trade routes. Economic factors played a crucial role in shaping the relations and tensions between different groups, underscoring the importance of trade and access to resources in historical conflicts.