In 1521, thousands of people in the aztec capital of tenochtitlán were killed by smallpox during an epidemic that swept through the city. this outbreak was one example of
a. the major impact that the arrival of europeans had on native american civilizations.
b. the lack of native american medical technology before the arrival of the europeans.
c. the problems with sanitation in native american settlements before the arrival of the europeans.
d. the new disease that europeans faced when they first encountered native american civilizations.