How did population decline affect the native Americans

Depopulation from disease. The earliest European immigrants offered two principal explanations for the population decline of the American natives. ... The most devastating disease was smallpox, but other deadly diseases included typhus, measles, influenza, bubonic plague, mumps, yellow fever, and whooping cough.

Explanation:

answer; the intervening variable;

answer; gender,race,age,/// (d) all of these;