The correct answer is:
a Each system developed as a way of ensuring labor for colonizers. Each system was based on race, which has had long-term effects on the structure of the societies of the Americas.
Both chattel slavery and the encomienda system were established to provide labor for European colonizers, with chattel slavery relying primarily on the forced labor of Africans and the encomienda system exploiting Indigenous populations. These systems were deeply intertwined with ideas of race and resulted in profound and lasting social, economic, and cultural impacts across the Americas.