Answer:
C. American Indian populations were decimated by diseases brought by the Europeans.
Step-by-step explanation:
The effects of each "world's" diseases were not the same. As more Europeans were entering into the New World and settling, the Native populations were suffering as a result from direct contact with the settlers as well as indirect (through trades with other tribes). As their body did not have the proper antibodies, nor did they have medicine, they suffered much more drastic effects when contracting the diseases. On the other hand, the one well known disease brought from the new world to the old was syphilis, which can cause damage to the heart, brain, bones, etc. However, the effects of the diseases were much more prominent in the wider range of diseases and death toll for the Native Americans, rather than for the Europeans.
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