Using the diagram above, a key characteristic of aquatic dead zones is ________ and which activities is most directly related to the dead zones in the Gulf of Mexico just west of the Mississippi River?
A) high concentration of dissolved oxygen, and extensive shrimp fishing
B) low concentration of dissolved oxygen, and farming in the Midwest
C) high concentration of nitric oxides and burning coal to generate electricity in the Northeast.
D) low concentration of dissolved phosphates an Barge traffic on the Mississippi River