Answer:
B) Absence of native grasses
Explanation:
The grasses, which acted as a windbreak and whose roots anchored the soil in place, were overgrazed and/or removed to allow for farming. Once a few years of severe drought affected the area, any wind storm was able to blow the topsoil away, rendering the farm land of the Great Plains virtually unusable in many areas. Ground cover is an essential part of sustainable agriculture.
A virus is not a bacteria, but it is caused by a bacteria. A virus causes the immune system to weaken.
When the body becomes dehydrated, a chemical signal is sent that causes nephrons in the kidneys to absorb more water and excrete more salts. This is an example of a <em>D Feedback loop</em>.
Answer: 4. Problem solver
Explanation: you're working to fix a known problem
