Concept:The collapse of the old Oyo Empire was caused by combined pressures from within and outside the kingdom.
Explanation:The empire experienced serious internal political struggles, such as disputes among chiefs and the weakening central authority.
At the same time, external invasions and rebellions, especially the revolt led by Kakanfo Afonja, increased the pressure.
These internal and external crises overwhelmed the empire, leading to its fall in the late 18th century.
A single event, like Afonja's revolt, was not the only cause; it was part of the wider crisis.
Answer:B. Internal and external crisis