Final answer:
Europeans deemed Africans as more suitable labor due to their immunity to European diseases and their unfamiliarity with the American landscape, which made them easier to control.
Step-by-step explanation:
Europeans saw Africans as a better source of labor than Native Americans for several reasons. Key among these reasons was that Africans had developed immunity to many European diseases such as smallpox over centuries of interaction, making them less susceptible to the illnesses that devastated the Native American populations. Additionally, Africans were strangers to the Americas, meaning they had no allies or places to hide which would facilitate their capture and control. Furthermore, the resistance of Africans to diseases like malaria and yellow fever, prevalent in the Caribbean due to the slave trade itself, made them more suitable for labor in tropical climates where Europeans suffered high mortality rates.