which best describes why American Indian groups were vulnerable to European diseases?

They lacked the necessary vaccinations

They were unfamiliar with all diseases

They failed to take preventative measures

They lacked immunity to these diseases

Respuesta :

they lacked immunity to these diseases.
before the europeans, the american indians hadn’t come in contact with these diseases that were part of a different area of the world. as a result, many american indians died.
D they lacked immunity