Which of the Following Is Not a Way That an Individual's

Which of the following is not a way that an individual's grades are related their peers' grades?

A) Students with best friends who achieve high grades in school are more likely to show improvements in their own grades than are students who begin at similar levels of achievement but whose friends are not high achievers.
B) When adolescents' grades improve, they tend to befriend more high-achieving classmates.
C) When adolescents' grades drop, they tend to befriend lower-achieving classmates.
D) All of these are ways that students' grades change in relation to the grades of their friends.