GRE Logical Reading: ETS-GRE逻辑单题ETS - E4VU01D3OQZ2UGZ9J$

Which of the following, if true, most seriously undermines the researcher's hypothesis? A. More carbohydrates are eaten per capita in nations where the government spends more per capita on public exercise programs. B. Children who do not participate in organized sports tend to eat fewer carbohydrates than children who participate in organized sports. C. Consumption of increased amounts of carbohydrates is a popular tactic of runners preparing for long-distance races. D. Periods of physical growth require a relatively higher level of carbohydrate consumption than otherwise. E. Though carbohydrates are necessary for the maintenance of good health, people who consume more carbohydrates are not necessarily healthier.