Hello there, I'm currently struggling with a particular question on one of my statistics assignments. The question is as follows:

Upon completion of studying each chapter in their social studies course, students are asked by their teacher to write an essay on their analysis of the chapter content and how they could apply the concepts in real life. To encourage her students to perform well on each essay, the teacher gives a token if the student obtains a mark of at least 90%. Students, particularly those not receiving a token, could attempt for one at the end of each subsequent chapter. Then, to receive a special prize at the end of the term, a student should have at least 10 tokens to exchange for the prize. Based on this study, identify the following:

Independent variable

Dependent variable

By my current understanding from my assigned readings, the independent variable is something that is being manipulated, and also divides two different groups, which is what confuses me in this particular question. As for the dependent variable, I feel like the most likely answer are the student's test scores, based on context.

I'd greatly appreciate help on this question, thanks.