Which evidence best supports the claim that participating in a team sport improves students’ academic performance?
A) Some teachers at our school think that participating on a team is not always the best way to improve grades.
B) Advertising posters made by a sportswear company suggest that all athletes are exceptional students.
C) A chart based on a long-term study illustrates the direct relationship between team membership and above-average grades.
D) Coach Herbert has encouraged every student at Wilson Middle School to join the cross-country team this spring.