Final answer:
Trade, specifically the Trans-Saharan trade routes, facilitated the spread of Islam across Africa by allowing Arabic traders to promote their religious beliefs along with goods. This led to the adoption of Islam by local rulers and communities, resulting in its widespread influence.
Step-by-step explanation:
Trade played a significant role in facilitating the spread of Islam across Africa. The Trans-Saharan trade routes, for example, connected North Africa with West Africa, providing a means for Arabic traders to travel and promote Islamic teachings. These traders carried goods, such as textiles, gold, and salt along with their religious beliefs, thus introducing Islam to different African regions. As a result of this trade, many local rulers and communities adopted Islam, leading to its widespread influence across the continent.
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