Leopold II implemented a forced-labour system in the Congo that was quickly copied by other European colonial powers. This brutal practice was a catastrophe for the population of the Congo, and Leopold was eventually forced to give up his hold on the colony.
The answer is b!!!!!!!!!!!!!!!!!!
Improper nutrition,unsanitary,living conditions,and excessive labor made them more susceptible to diseases than their owners;the death rates among the slaves were significantly higher due to diseases.