The Graph Below Shows the 16-Hour Mortality Resulting from Exposing

Multiple Choice

The graph below shows the 16-hour mortality resulting from exposing talapia to different concentrations of the dinoflagellate Pfiesteria.
Had high mortality occurred in the control group it would indicate that

A) a more robust fish species should be used; the experiment had a fundamental design flaw.
B) the talapia had an undiagnosed preexisting illness at the beginning of the experiment.
C) Pfiesteria was not the toxic agent responsible for the death of the fish.
D) talapia is not suitable for captive experiments.