Answer:
B. The findings are not meaningful or valid because of the way she designed her study.
Explanation:
In a scientific experiment, a control group is a group of individuals/subjects that do not receive the experimental treatment. The control group is used to determine how much of an impact a treatment (in this case, cadmium intake) has on the variables being examined in the participants who are subjected to the experimental treatment. In any experiment, it is imperative to include a control group in order to validate experimental results. In this case, it is not possible to confirm that the loss of weight and abnormal hormone levels are due to cadmium uptake because only a control group would elucidate the contribution of cadmium intake on the variables being tested.
