What industry contributed most to the economy of the kilwa malindi mombasa and sofala?

The economy of Kilwa, Malindi, Mombasa, and Sofala was predominantly driven by the trade industry, particularly in spices, gold, ivory, and textiles. These coastal cities served as vital trading hubs along the East African coast, facilitating commerce between Africa, the Middle East, and Asia. The ports in these regions enabled the exchange of goods and cultural interactions, significantly enhancing their economic prosperity during the medieval period. Additionally, fishing and agriculture also played important roles in supporting local economies.