On What Basis Did Bartolomé De Las Casas Plead to the Spanish

On what basis did Bartolomé de Las Casas plead to the Spanish crown to end the exploitation of Native Americans?

A) He argued that the Native Americans were highly intelligent, deserved decent living conditions and the opportunity to become Christians.
B) He claimed that if the Native Americans were treated better they would perform better and increase profits for their managers.
C) He contended that the Native Americans were not use to such hard labor, and managers would suffer diminishing returns if they continued to exploit the native workers.
D) He believed that the Native Americans were distant relatives of the Europeans and should be treated accordingly.
E) He recognized the potential of the Native Americans and warned the Spanish crown not to antagonize a future, powerful enemy.