Concept:The Mfecane refers to the violent upheavals and migrations among southern African peoples caused by Shaka’s conquests and military expansion.Explanation:Shaka built a highly aggressive Zulu military machine and launched widespread campaigns to subjugate neighboring groups.These campaigns triggered wars, displacement, and chaos across the region, commonly known as the Mfecane.Although factors like rivalry or pressure on resources existed, the immediate driving force was Shaka’s intense military ambition.Answer:D. Shaka’s inordinate military ambition.