The most accurate response is: "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."
Chattel slavery and the encomienda system were both systems of labor exploitation utilized by European colonizers in the Americas. Chattel slavery involved the forced labor of African slaves and was racially based, embedding racial hierarchies into the social structure of the Americas. The encomienda system similarly relied on the forced labor of Indigenous peoples, with rights granted to colonizers to exploit Indigenous labor while providing them nominal protection and Christianization. Both systems had profound and lasting impacts on the demographic, social, and economic structures of the Americas, leading to systemic inequalities and shaping race relations that persist to this day.