The statement that most accurately evaluates the development of feudalism as a power structure is: "Feudalism developed as an effective way to provide stability during a chaotic period."
Feudalism arose in Europe following the collapse of the Roman Empire and during a time of turmoil, invasions, and decentralized governance. It provided a structured way to maintain order, security, and land management through a system of mutual obligations between lords and vassals. The other statements either oversimplify or misrepresent the complex historical context of feudalism.