There numerous of them but some of them would be contaminated soil which can be followed with altered soil chemistry that contains fewer soil organisms that are essential. The third one would be surface runoff due to extensively modified hydrology of the area.
Natural selection helps the anteater get food easier than others.
Sample b is the control group because it’s the group not being tested and being kept the same.
First one is Model and second one is Inference
It is called a derived character. Hope this helps! (:
