In one experiment, the first group of subjects ingested a large amount of artificial sugar, while the second group did not consume sugar. It was found that people who ate sugar had lower cognitive ability than those who did not. The person's cognitive ability was comparable before the trial. This experiment illustrates:. ["Artificial sugar definitely hurts people's cognitive ability.", 'This ingredient contained in artificial sugar is also found in most daily foods.', 'The amount of sugar ingested by the first group of subjects did not exceed the safe range prescribed by the health department.', "Some ingredients in artificial sugar may affect people's cognitive ability."]