Read the following paragraphs and answer the question.

     While both groups did better than chance would predict, nearly half the participants in each group made the wrong choice two or more times. Two people got all four samples wrong. Overall, half the participants did about as well on the last round of tasting as on the first, so fatigue, or taste burnout was not a factor. Our preference test results suggest that only a few Pepsi participants and Coke fans may really be able to tell their favorite brand by taste and price.

The statistics recorded in the preference tests show（）.