A twelfth-century king was merely a 'lord of lords', whereas a fourteenth-century king functioned as a territorial sovereign. What fundamental shift distinguishes these two roles?

B. Sovereigns drew income from general taxation rather than private estates

Kings originally sustained their households from personal domain yields; territorial sovereignty emerged as rulers instituted general taxes and permanent administrative bodies over all subjects. Assemblies arose to negotiate this very change, rather than supporting early feudal lordship.