The Spanish conducted slave-raiding expeditions along the east coast before the Naváez and de Soto expeditions to Florida, a practice that had become widespread throughout the Spanish new world since the Columbian voyages. Queen Isabella forbade the practice, but the Spanish monarchs agreed in 1503 to what was later called the encomienda system. Under this system, Spaniards would be granted an allotment of Indians who were to be protected and Christianized. In essence the natives became forced laborers who worked the land, labored in mines, and constructed public buildings. –Library of Congress "Parallel Histories: Spain, United States and the American Frontier” The transition from slave-raiding to the encomienda system is one example of how Europeans A) created new and advanced systems that elevated the economic status of native peoples in the Americas. B) denounced and refused to participate in the subjugation of native peoples in the Americas. C) adapted their principles to new and unfamiliar surroundings and situations. D) established and maintained separate and isolated colonies in the Americas.