Concept: Identify the most influential ruler of Kanem-Borno based on territorial expansion and legacy.Explanation: Mai Dunama Dibbalemi ruled the Kanem-Borno empire during the 13th century. He is celebrated as the greatest ruler because he expanded the kingdom northward and northeastward into the desert. This expansion greatly increased the empire's size and influence. He also strengthened Islam and established diplomatic and trade links across the Sahara. His military campaigns made Kanem-Borno one of the most powerful empires in the central Sudan. Although other rulers such as Mai Njimi Balongo and Mai Gazargamo contributed to the empire, none matched Dibbalemi's far-reaching conquests. Therefore, historians commonly regard him as the greatest leader of the empire.Answer: B. Mai Dunama Dibbalemi