According to a recent study, 26 percent of women and 19 percent of men

Premise: According to a recent study, 26 percent of women and 19 percent of men in the United States said they were on a diet, down from 35 percent of women and 26 percent of men in 1990.
Conclusion: As a result, obesity in the United States has increased from 15.6 percent in 1995 to 23.9 percent today.

According to this argument, Because the percentage of men and women in the United States on a diet has decreased, the rate of obesity in the United States has increased.
In arriving at this conclusion the author has made several assumptions such as there are no alternate causes for the increase in obesity, the people haven't started doing something else keep their weight in check, etc.

Which of the following statements would be the most helpful in evaluating the validity of this conclusion?


A. Although the percent of people who are dieting has decreased, 60 percent of U.S. adults say they would like to lose 20 pounds.
The argument is not about what the people want, it is about the increase in the rate of obesity.

B. It is estimated that 60 percent of the adult population in the United States is overweight.
This answer choice doesn't affect the strength of the argument. We already know that the rate of obesity has increased.

C. Weight Watchers is among the most popular diets in the United States.
This answer choice doesn't affect the strength of the argument. We already know that the percentage of people on a diet has decreased. Knowing what the most popular diet is doesn't help us evaluate the argument.

D. Diets have only a 5.2 percent success rate; within three to five years, almost all dieters are back up to original body weight.
This answer choice does have an affect on the strength of the argument. This answer choice shows that being on a diet has a very low success rate, which implies that reduction in the percentage of people on a diet wasn't the factor that caused an increase in the rate of obesity.

E. In 2001, the U.S. Surgeon General declared an obesity epidemic, stating that roughly 300,000 deaths a year can be attributed to obesity.
This answer choice is incorrect for the same reason as (B)

Understanding the argument -
According to a recent study, 26 percent of women and 19 percent of men in the United States said they were on a diet, down from 35 percent of women and 26 percent of men in 1990. - Facts. It talks about Diet.
As a result, obesity in the United States has increased from 15.6 percent in 1995 to 23.9 percent today. - Conclusion. Talks about Obesity.

There is a shift from Diet in premises to Obesity in the Conclusion. In the evaluate argument, we need to check the validity of the conclusion. So, we need to check whether there is a connection between "Diet" and "Obesity."

Option Elimination -

A. Although the percent of people who are dieting has decreased, 60 percent of U.S. adults say they would like to lose 20 pounds. - what they would like is not the scope of the argument. The scope of the argument is to check the connection between "Diet" and "Obesity." Out of scope.

B. It is estimated that 60 percent of the adult population in the United States is overweight. - ok. But what is the connection between "Diet" and "Obesity"? Out of scope.

C. Weight Watchers is among the most popular diets in the United States. - Ok. But what is the connection between "Diet" and "Obesity"? Out of scope.

D. Diets have only a 5.2 percent success rate; within three to five years, almost all dieters are back up to original body weight. - ok. It says that Diet has a low success rate, and within 3 to 5 years, people come back to their original body weight. This weakens the connection between "Diet" and "Obesity." If this option is true, then the Conclusion is weakened and not valid.

E. In 2001, the U.S. Surgeon General declared an obesity epidemic, stating that roughly 300,000 deaths a year can be attributed to obesity. - declaring "obesity" an emergency doesn't establish the connection between "Diet" and "Obesity." Out of scope.