The nurse should suspect of a fractured jaw.
The crepitus is a common sign of bone fracture and it's heard when the fractured surfaces of two broken bones rub together.
Also If there is a severe jaw fracture, the patient might experience limited ability to move the jaw or be unable to move it at all.
The important role of the atmosphere is to supply oxygen, water, carbon dioxide and nutrients. It also protects all living things from extreme temperatures and radiation (protects us from harmful solar rays).
Answer: I think that it would be C because blooms are due to eutrophication, which means that there are high levels of phosphate in the water. Phosphate is a main ingredient in pesticides, which can run-off into rivers.