A certain pharmaceutical firm claims that its dietary supplement, Diet

There is one massive confounding variable in the study: the 2-hours of physical training with a professional trainer (that's quite a nice perk for taking part in the study ). For the researchers to claim that the improved benefits were from the use of Dietol is highly suspect. Imagine your friend tells you that he/she has been working out 2-hours a day with a professional trainer. And every morning they say a magic chant. If you congratulate him/her on her new svelte form and ask what the trick was, you would definitely be skeptical if he/she answered: my magic chant.

This study, however, is no different. Therefore, we would need a study that either eliminate the 2-hour training sessions, or tests 2-hour training sessions without Dietol to see the effects. The latter will help us evaluate the conclusion because now we can clearly determine the effects of 2-hour daily training. Therefore the answer is (C).

Hope that helps .

The crux of the argument is weight loss and increase in endurance happened because of Dietol. Exercise was not a contributory factor.


A. What was the daily dose of Dietol that the subjects were required to take?
Daily dosage is irrelevant to the conclusion.

B. What was the maximum weight lost by any participant during the 9-week program?
Maximum weight loss does not have any effect on the conclusion


C. What would be the average weight loss and the improvement in endurance in a group of subjects with similar characteristics involved in the same physical fitness program but not taking Dietol?
Correct - If the group has HIGH weight loss, conclusion is weakened. If the group has negligible weight loss, then the conclusion is strengthened.



D. What was the average age among the subjects participating in the experiment?
Age is irrelevant to the conclusion.

E. Did the majority of subjects experience a significant improvement in physical strength?
Trap choice. Endurance is replaced by strength. But again no impact on conclusion - because Dietol is supposed to do 2 things - weight loss and increase in endurance.

To evaluate the conclusion of the pharmaceutical company, we need information that helps us determine whether Dietol is the cause of the observed weight loss and improved physical endurance in the subjects. Let's analyze each of the answer choices:

A. What was the daily dose of Dietol that the subjects were required to take?
- This question is important because it helps us understand the dosage of Dietol. Knowing the dosage can help us determine whether the observed results are due to the supplement or other factors. However, this question alone doesn't provide a complete evaluation of the conclusion.

B. What was the maximum weight lost by any participant during the 9-week program?
- This question may be interesting but doesn't directly address the effectiveness of Dietol or whether it caused the weight loss. It focuses on individual outliers rather than the overall effectiveness.

C. What would be the average weight loss and the improvement in endurance in a group of subjects with similar characteristics involved in the same physical fitness program but not taking Dietol?
- This question is highly relevant as it provides a basis for comparison. It allows us to see if the improvements observed in the Dietol group are significantly different from those in a control group. This information can help evaluate the effectiveness of Dietol.

D. What was the average age among the subjects participating in the experiment?
- While age can be a factor in weight loss and endurance, it's not as directly relevant to the evaluation of the pharmaceutical company's claim. Other factors like diet and exercise routines might be more important.

E. Did the majority of subjects experience a significant improvement in physical strength?
- This question touches on another aspect of the results, but it doesn't directly address whether Dietol is the cause of the improvements in weight loss and endurance. It also doesn't provide a basis for comparison.

Among the given options, question C is the most helpful in evaluating the conclusion of the pharmaceutical company because it addresses the need for a control group to compare the effects of Dietol with a similar group of subjects who did not take the supplement. This would help determine whether Dietol is responsible for the observed results or if other factors, such as the fitness program, played a significant role in the outcomes.