Which of the Following Statements Comparing Freshwater and Marine Environments

Which of the following statements comparing freshwater and marine environments is true?

A) The marine environment is generally far more stable than the freshwater environment.
B) A seasonal thermocline may develop in a marine environment, but not a freshwater environment.
C) Benthic zones occur in marine environments, but not in freshwater environments.
D) In a marine environment, the pelagic zone usually has the highest species diversity, while in freshwater environments, diversity in the pelagic zone is usually low.
E) In marine environments, phosphorus is usually the principal factor limiting microbial growth. In freshwater environments, iron is usually the most principal limiting factor.