During the sixteenth and seventeenth centuries, the major reason for the high death rate among Native Americans from disease was

a. warfare.

b. lack of immunities.

c. malnutrition.

d. overwork.

During the sixteenth and seventeenth centuries, the major reason for the high death rate among Native Americans from disease was " b. lack of immunities," since the Europeans carried diseases that the Natives had never come into contact with before.