Concept:The Old Oyo Empire was ruled by a supreme monarch known as the Alaafin.Explanation:The Alaafin served as the political and spiritual head of the empire.He held ultimate authority over governance and the people.The Oyomesi, led by the Bashorun, acted as an advisory council with checks on the Alaafin's power.The Aremo was the heir apparent, not the political head.Thus, the political head of the Old Oyo Empire was the Alaafin.Answer:D. Alaafin