Respuesta :
Starting in the Middle Ages, Swahili became the "lingua franca," or common language, in trading ports along the eastern coast of Africa because the native Africans controlled the trade that took place in their ports.
- Swahili is an ethnic group that develop on the East coast of Africa when Arab traders began to settle there for trade.
- Many merchants from Arabia and Asia stayed in the city-states of East Africa, which led to a new and different ethnic group known as Swahili.
- Swahili, steadily grew and become economic power by the 1400s.
Therefore, we can conclude that in the Middle Ages, the Swahili language became common in trading ports.
Thus option B. is the correct answer.
Learn more Swahili here:
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