Question

Recent research indicates that excessive consumption of processed foods is linked to an increased risk of obesity. A five-year study tracked two groups: one that regularly consumed processed foods and another that followed a whole-foods-based diet. The study found that the processed-food group had a 25% higher rate of obesity by the end of the study. Therefore, the study concluded that processed food consumption directly causes obesity.
Which of the following, if true, most strengthens the argument above?

• A. Some participants in the whole-foods group occasionally consumed small amounts of processed foods
• B. Both groups were matched for physical activity levels, age, and overall caloric intake during the study period
• C. Other studies have shown that regular exercise reduces the risk of obesity, regardless of diet
• D. Processed foods are often high in sugars and unhealthy fats, which contribute to weight gain

Answer 1

Answer: (B)

Both groups were matched for physical activity levels, age, and overall caloric intake during the study period

Answer 2

Option (b) strengthens the argument because it shows that the only difference between the two groups was their diet, ruling out other factors like physical activity or caloric intake that might have contributed to the higher obesity rate in the processed-food group.
Thus, the correct answer is Option (B).