Answer:His son Sonni Baru (reigned 1493), who sided completely with the pastoralists, was deposed by the rebel Muḥammad ibn Abī Bakr Ture, also known as Muḥammad I Askia(reigned 1493–1528), who welded the central region of the western Sudan into a single empire. He too fought the Mossi of Yatenga, tackled Borgu, in what is now northwestern Nigeria (1505)—albeit with little success—and mounted successful campaigns against the Diara (1512), against the kingdom of Fouta-Toro in Senegal, and to the east against the Hausa states. In order to win control of the principal caravan markets to the north, he ordered his armies to found a colony in and around Agadez in Aïr. He was deposed by his eldest son, Musa, in 1528.Throughout the dynastic squabbles of successive reigns (Askia Musa, 1528–31; Bengan Korei, also known as Askia Muḥammad II, 1531–37; Askia Ismail, 1537–39; Askia Issihak I, 1539–49), the Muslims in the towns continued to act as middlemen in the profitable gold trade with the states of Akan in central Guinea. The peace and prosperity of Askia Dāwūd’s reign (1549–82) was followed by a raid initiated by Sultan Aḥmad al-Manṣūr of Morocco on the salt deposits of Taghaza. The situation, which continued to worsen under Muḥammad Bāni (1586–88), culminated disastrously for Songhai under Issihak II (1588–91) when Moroccan forces, using firearms, advanced into the Songhai empire to rout his forces, first at Tondibi and then at Timbuktu and Gao. Retaliatory guerrilla action of the pastoral Songhai failed to restore the empire, the economic and administrative centres of which remained in Moroccan hands.
So B or D.
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