Luis is an avid baseball player. For his science project, he decides to test which type of bat is best for hitting home runs. Luis prefers to use an aluminum bat when he plays, so he hypothesizes that he will hit more home runs using an aluminum bat than a wooden bat. During batting practice, he tests his hypothesis. He hits a baseball with a wooden bat and it lands near first base. He swings the aluminum bat with all his might and the ball sails over the back fence. He concludes that the data supports his hypothesis.

Which of the following statements reveals Luis' experimental bias

A. He swings the aluminum bat with all his might.

B. He will hit more home runs using an aluminum bat than a wooden bat.

C. Luis is an avid baseball player.

D. He hits a baseball with a wooden bat and it lands near first base.