The plague bacterium Yersinia pestis,is well-known for the high death toll it caused in Europe during the Middle Ages.Upon introduction to North America,this disease

A)caused high death rates in isolated human communities.
B)did not spread because humans are immune to it.
C)spread to other species, such a native prairie dogs, which suffered high mortality rates.
D)affected predators of prairie dogs, soil chemistry, and plant growth.
E)C and D