Historical Causes of Diffusion Practice Test

From the 700s to the 1400s, merchant networks across the Indian Ocean linked East Africa, Arabia, South Asia, and Southeast Asia. Seasonal monsoon winds made regular voyages possible, and port cities grew where traders exchanged spices, textiles, and ceramics. Along with goods, merchants carried languages, accounting practices, architectural styles, and religions, helping Islam spread along many coastal trading communities. Which historical cause of cultural diffusion is most directly illustrated?

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Across the Trans-Saharan routes from the 800s to the 1500s, camel caravans linked West African states with North Africa and the Mediterranean world. Merchants exchanged gold, salt, and textiles, while also transmitting Arabic as a written language, commercial legal norms, and Islamic scholarship into trading towns such as Timbuktu. These urban centers became hubs where ideas traveled alongside commodities. Which historical cause of cultural diffusion is most clearly demonstrated?

(Secondary-source excerpt embedded above.)