A similarity between the ancient western African kingdoms of Mali Ghana and Songhai is that these kingdoms?

A similarity between the ancient Western African kingdoms of Mali, Ghana, and Songhai is their reliance on trade, particularly in gold and salt, which significantly contributed to their wealth and power. Each kingdom developed along key trade routes, facilitating cultural exchanges and the spread of Islam. Additionally, they all had centralized political structures and strong leaders who helped to unify and expand their territories. These kingdoms also prioritized education and scholarship, leading to the establishment of centers of learning, such as Timbuktu.