How Did Justifications for Slavery Change from the Fifteenth to Eighteenth

How did justifications for slavery change from the fifteenth to eighteenth century?

A) Arguments supporting slavery increasingly relied on economic justifications of the superiority of slave labor.
B) Arguments supporting slavery drew increasingly on the need to civilize the savage Africans and less on ideas of race.
C) Arguments supporting slavery began to focus more on science and nature and less on religion.
D) Arguments supporting slavery emphasized the political needs of empires rather than cultural or religious issues.