While serfdom and indentured servitude were justified mostly by economic principles, slavery and the encomienda system were justified most by
a. racist principles
b. regional practices
c. religious principles
d. agricultural practices

While serfdom and indentured servitude were justified mostly by economic principles, slavery and the encomienda system were justified most by "a. racist principles," since many slaveowners believed that African Americans could not "help" themselves. 

You don’t have to names or other options up here so idk dude