Refer to the Graph Below Showing the Results of a Study

Multiple Choice

Refer to the graph below showing the results of a study that exposed male frogs to atrazine, a chemical used in killing weeds in agricultural areas. According to the data in the graph, higher atrazine concentrations do not result in a higher rate of gonadal abnormality.Which conclusion can be drawn from these results?

A) Low levels of atrazine are not as dangerous to amphibians as high levels of atrazine.
B) A dosage of 15 ppb would cause a rate of abnormality between the one caused by the 0.1 ppb dosage and the one caused by the 25 ppb dosage.
C) The effect of the atrazine exposure is not proportional to the level of exposure.
D) Atrazine is only hazardous in a natural ecosystem, where it is naturally diluted in the waterways.
E) Atrazine usage should be banned.