Final answer:
The political system characterized by decentralized government, loyalty and service, code of chivalry, and military elite is feudalism, common in medieval Europe. option a.
Step-by-step explanation:
The political system best described by the factors of a decentralized government, based on loyalty and service, adherence to a code of chivalry, and a military elite is most likely feudalism. This was a system that flourished in medieval Europe and in other parts of the world, where land was held in exchange for service, typically military service to a higher lord or monarch. Loyalty and service were the foundations of this system, with a socially-recognized code of chivalry dictating the conduct of the military elite, also known as knights. In feudal societies, political power was not centralized in a single government but was dispersed among numerous lords who ruled their own lands as sovereign entities.