Final answer:
The title of the head of an Oba in the Benin Kingdom is 'Oba', which represents the king or ruler, distinct from the 'Iyoba', which refers to the Queen Mother.
Step-by-step explanation:
The title of the head of an Oba in the Benin Kingdom is Oba. This title signifies the ruler, or king, of the Kingdom of Benin, which is located in present-day Nigeria. The Oba has been a central figure throughout the kingdom's history and is treated with great reverence as both a political and spiritual leader. Notable Obas included Ewuare the Great, who reigned from 1440-1473, and expanded Benin into a formidable empire. Meanwhile, the Iyoba you mentioned in the question refers to the Queen Mother or mother of the king. This can be exemplified through the unique art produced in the kingdom, such as the Queen Mother Pendant Mask (Iyoba), dating back to the 16th century.