A teacher tells his class that whoever scores a 90 percent or higher will be allowed to go on the field trip. Which of the following BEST describes the field trip?

The field trip can be best described as a reward or incentive for academic achievement. It serves to motivate students to perform well in their studies, specifically by aiming for a high score. Additionally, it creates a sense of exclusivity, as only those who meet the specified criteria will be able to participate.