A certain baseball team has just completed its season. In stadiums that seat 20,000 or fewer people, the team averaged 1 home run per game; in stadiums that seat between 20,000 and 40,000 people, the team averaged 2 home runs per game; and, in stadiums that seat 40,000 or more people, the team averaged 3 home runs per game. Obviously, the excitement of playing in front of large crowds motivated the team to hit more home runs.

Assuming that all stadiums during the season were filled to capacity, which of the following, if true, most undermines the argument above?
The team's leading home run hitter hit more home runs in mid-sized stadiums than in large stadiums.
The fans in the larger stadiums often cheered against the team.
The team averaged only 2 home runs per game when playing in the league’s largest stadium.
In order to create seating for the additional fans, the outfield walls in the larger stadiums were constructed closer to home base.
The team’s announcer cited crowd noise as a major motivator for the team.